* feat(studio): glue API coexistence layer for the NLE swap
What: extends 21 glue files so the OLD timeline/canvas engine and the NEW
NLE components type-check side by side: playerStore (multi-select setters,
zoom pin, snap toggle, non-reactive scale scratch), drag-state types gain
optional NLE fields, timelineLayout/timelineAssetDrop/timelineEditingHelpers/
timelineEditing/timelineElementHelpers/studioHelpers/assetHelpers gain the
NLE exports, DomEditOverlay + gestures + AssetContextMenu + Timeline props
gain optional callbacks/params, contexts gain *Optional hooks, and
TimelineEditCallbacks.onMoveElements becomes a bivariant method accepting
both engines' change shapes. patchDocumentRootDuration's test rides along.
Why: this is the keystone that dissolves the old "welded glue" problem —
every symbol the NLE components need is ADDED next to what the old engine
still uses, so the engine components and the swaps can land as separate
reviewable PRs.
How: 15 authored intermediate files (main content + additive symbols; no
behavior changes — new fields optional, new callbacks unused until wired)
plus 6 files whose final content is already purely additive. New exports
without consumers yet carry TEMP(studio-dnd) ignoreExports entries, removed
by the app-shell swap.
Test plan: tsc --noEmit in studio + studio-server (verifies BOTH engines
compile); bunx vitest run (full suite green incl. the 6 new
patchDocumentRootDuration tests); fallow audit clean.
* feat(studio): timeline interaction hooks and lanes component (unwired)
What: the timeline-side wiring layer, unwired: TimelineLanes (the lane
renderer driving drag/resize/marquee), timelineMarquee (+tests),
useTimelineStackingSync, useTimelineGeometry, useTimelineEditPinning,
useTimelineEditingDrops.
Why: everything between the pure drag math and <Timeline> itself; the
timeline-glue swap PR then only rewires Timeline/TimelineCanvas onto these.
How: new files, tsc-clean against the coexistence layer. Unwired components
carry TEMP(studio-dnd) entry registrations, removed at the app-shell swap.
Test plan: bunx vitest run timelineMarquee.test.ts; tsc --noEmit; fallow
audit clean.
* feat(studio): NLE shell assembly (unwired)
What: EditorShell (the full editor layout replacing NLELayout +
StudioPreviewArea), TimelinePane (timeline host with sub-comp rebasing) and
useTimelineEditCallbacks (the callback bag bridging store edits to the
timeline), all unwired.
Why: the shell that App swaps to in the final step; reviewing it standalone
keeps that swap PR small.
How: new files against the coexistence layer; TEMP(studio-dnd) entries
until App mounts EditorShell in the app-shell swap.
Test plan: tsc --noEmit; bunx vitest run (suite unchanged); fallow audit
clean.
* feat(studio): timeline glue swap — Timeline/TimelineCanvas onto the NLE engine
What: flips the timeline glue to its final form (23 files): Timeline and
TimelineCanvas rebuilt on TimelineLanes/TimelineOverlays, useTimelineClipDrag
drives preview/commit through the new drag engine, range selection goes
multi-select, playback loop moves to useTimelinePlayerLoop. Deletes the 9
old-engine files this orphans (group drag, marquee selection, snap targets,
layer gutter, selection overlays + their suites) — each is compile- or
gate-forced by this swap, verified by probe.
Why: second swap step; timeline-only, canvas and App untouched.
How: modified files to final content + forced deletions.
playerStore/timelineEditing/timelineCallbacks stay at their coexistence
form until the app swap (the old App still runs on them).
Test plan: tsc --noEmit; bunx vitest run (full suite); fallow audit clean.
* feat(studio): clip thumbnail modules
What: ImageThumbnail (+tests) and thumbnailUtils (+tests) — frame decode
with SVG/AVIF format fallbacks and rounded-corner clipping — plus
VideoThumbnail updates.
Why: the decode layer for timeline clip thumbnails, ahead of the visual
refresh that renders them.
How: new modules + one modified file; purely presentational.
Test plan: bunx vitest run on both test files; tsc --noEmit; fallow audit
clean.
* feat(studio): assets/blocks panel behaviors + preview helpers
What: blocks tab install flow, right-panel and global drag-overlay polish,
music beat analysis and clip-content rendering hooks, and the
preview-helper utilities backing asset preview.
Why: completes the studio NLE stack on top of the visual refresh.
How: modified files only (kept as one PR: splitting further would produce
sub-150-LOC fragments of interdependent panel glue).
Test plan: bunx vitest run studioPreviewHelpers/studioUrlState suites; tsc
--noEmit; fallow audit clean.
* fix(studio): restore timeline playback loop
* fix(studio): restore missing GSAP helpers module
* refactor(studio): split timeline GSAP helpers
* style(studio): keep timeline helper under size limit
* fix(studio): restore timeline overlays module
* fix(studio): remove stale GSAP import
* fix(studio): restore canonical timeline dependencies
* style(studio): format restored timeline helpers
* style(studio): satisfy helper line limit
* fix(studio): repair rebuilt timeline integration
* feat(studio): complete rebuilt NLE cutover
* fix(studio): guard project and timeline race boundaries
* fix(studio): preserve graded resize and crop geometry
* fix(studio): log resize/rotate commit failures, move anchor accumulator to resize-local
* fix(studio): treat duration-0 tweens as static holds and settle resize position before persist
Instant holds (to()/fromTo() with duration 0) were classified as animated
tweens by every commit route, so resizing or rotating them converted the
hold into a corrupt duration-0 keyframes tween (new value at 0%, old at
100%) that GSAP drops; panel edits appended a losing set. A shared
isInstantHold() now routes them through the static replace-in-place path,
and percentage math guards zero-duration windows.
Separately, anchored-corner resizes painted 3-5 frames at the new size but
old position while the offset persist round-tripped the server. The commit
path now applies the corrected GSAP position synchronously before awaiting
the offset persist, mirroring the scale route's settle.
* feat(studio): gesture-transaction seam with commit observability
Introduce runGestureTransaction — one owner for a gesture commit's
settle -> persist -> record lifecycle. It settles the live DOM
synchronously before any async persist, folds every mutation into one
undo entry via a per-transaction coalesceKey, restores pre-gesture state
exactly once on failure, and asserts (dev console) + reports (PostHog:
commit_transaction / commit_invariant_violation / commit_transaction_failed)
that a persist never changes pixels. The box-size resize path is migrated
onto it; the ad hoc per-route coalesceKey/reload handling is removed.
Extract the resize draft-rect math into resizeDraft.ts to keep the
gesture-handler file under the size cap.
Also: keep url_hash telemetry to the route slug only (drop the query
string, which carried the user's selected element id/selector), and gate
the [hf-resize] diagnostics behind localStorage hf-resize-debug so they
ship as opt-in tracing rather than console noise.
* fix(studio): transaction owns the undo label
The coalesced history entry took the last sub-mutation's label, so a
resize surfaced as "Move layer" (the offset persist) in undo/redo. The
seam now stamps tx.label on every wrapped mutation, so the folded entry
reads as the gesture.
* fix(studio): atomic static size/position commits (no data loss)
Static resize/position holds updated an existing set via delete+add — two
undo entries, and a delete that succeeded before a failed add lost the
hold on disk. Use one in-place update-properties mutation when a set
exists (one undo entry, no partial-failure window). The keyframed-hold
heal that can't be expressed as a property update now adds before it
deletes, so any single failure leaves a recoverable duplicate, never a
lost hold. Transaction-owned commits are tracked via a WeakSet so the
heal path never double-wraps an already-wrapped gesture.
* fix(core): restore timed-clip visibility after a forced timeline rebind
__hfForceTimelineRebind force-rendered the re-registered timeline but never
re-ran the per-[data-start] visibility pass, so after undo or soft reload
every clip rendered regardless of its time window until a full page reload.
Extract the visibility loop into syncTimedElementVisibility and call it from
both syncMediaForCurrentState (unchanged) and the rebind.
* fix(studio): atomic z-order/keyframe/split commits, one undo entry each
Three edit-commit paths hardened onto the one-transaction invariant:
- Z-order reorder (useElementLifecycleOps): N per-element writes now fold
into one undo entry (coalesceMs Infinity) and, on a failed persist,
restore already-written files to disk so no partial reorder survives.
- Enable-keyframes (useEnableKeyframes/useGsapKeyframeOps): the intermediate
convert phase no longer full-reloads the preview (skipReload), killing the
black-flash remount; convert + edit share one coalesce key = one undo entry.
- Razor split-all (useRazorSplit): snapshot before the batch and restore on
any failure, so a mid-batch error never leaves un-revertable partial splits.
Shared file-history helpers (RecordEditInput, DomEditCommitBaseParams,
readProjectFileContent, restoreFilesToOriginal) dedupe the rollback/commit
logic across these paths. Commit options thread as one partial object rather
than field-by-field. Test setup extracted into colocated helpers.
* fix(studio): fold multi-step edits into one undo entry; guard text revert
- Gesture recording (useGestureCommit): the per-property-group commits now
share one coalesce key and only the last reloads, so a recording is one
undo entry and one preview reload instead of up to four.
- Delete selected keyframes (deleteSelectedKeyframes, split out of
timelineEditingHelpers): N removals fold into one coalesced undo entry
with a single reload.
- Text-field commit (useDomEditTextCommits): commitDomTextFields now uses
the same version-guarded revert as handleDomTextCommit, so a stale failed
commit can no longer stomp a newer successful one.
* feat(studio): batch a gesture's mutations into one atomic server write
A transaction that emits N mutations previously did N sequential POSTs,
each rewriting the file and soft-reloading — the root of the multi-phase
persist window. Add a gsap-mutations-batch endpoint that validates every
mutation up front, applies them in one in-memory rewrite chain, and writes
the file once (all-or-nothing: an invalid entry rejects the whole batch,
no partial write). The seam buffers a transaction's commits and, when more
than one targets the same file, dispatches a single batch — one write, one
history entry, one reload. The batch capability rides on the existing
commit-function reference; no option fields are threaded through callers.
* fix(studio): soften off-canvas indicator outline to 30% opacity
The dashed off-canvas selection outline at 60% was noisy with many
protruding elements on screen; drop the resting opacity to 30% (hover
still restores full opacity so it stays discoverable).
* fix(studio): drop off-canvas indicator outline to 10% opacity
Follow-up to the 30% softening — 10% resting opacity reads much calmer
with many protruding elements; hover still restores full opacity.
* fix(studio): gate [hf-commit] console traces to dev only
The start/settled/persisted/restore lifecycle traces logged on every
gesture commit in all environments — console noise for end users. Route
them through a dev-only traceCommit helper (matching the pixel-violation
error's existing DEV gate). The commit_* PostHog events stay always on;
they are the production observability, the console lines are a dev aid.
* fix(studio): count actual reloads, not softReload requests, in commit telemetry
A resize's size and offset persists both request softReload; the seam
counted each request, so a batched gesture reported reload_count 2 even
though the batch is one write and one reload. Compute the count from what
dispatchBufferedCommits actually did — one for a batch, the request count
for the sequential fallback.
* fix(studio): rotate hover + off-canvas overlays with the element; flicker-free crop
- Hover overlay applied the element's rotation only to the selection chrome,
not the hover box; it now rotates about center like the selection, via a
shared orientedGroupAwareOverlayRect router (one owner for rotation-aware
overlay geometry across hover/selection/off-canvas).
- Off-canvas indicator was axis-aligned; it now rotates with the element and
inverse-rotates the canvas-exclusion clip into the element's local frame,
so the protruding-sliver clip stays correct for rotated elements.
- Crop commit re-lifted the element only in the commit's .then(), so one
frame painted the cropped state (the flicker). Re-lift synchronously right
after onStyleCommit (which applies the clip before its first await), so the
cropped state never paints; the persisted file value is unchanged.
* fix(studio): address code-review findings across the commit-hardening campaign
Correctness (would ship green, bite under latency):
- Enable-keyframes phase 2 now carries coalesceMs: Infinity, so the convert
folds into one undo entry instead of splitting past the 300ms default.
- The SDK keyframe persist path forwards coalesceMs (CutoverOptions gains the
field); multi-keyframe delete and convert coalesce correctly when SDK-routed.
- Razor split-all's rollback is guarded so a failing restore can't swallow the
error toast that tells the user the split failed.
Simplification (single source of truth / no dead flexibility):
- Decompose resolveResizeDraftRect (drops a fallow-ignore suppression).
- Delegate the third readProjectFileContent copy to the shared helper.
- Inline setPatchFromUpdateProperties (its only caller passes one mutation).
- One toSdkPersistOptions translates gesture overrides to SDK options.
- Bundle the reorder-rollback deps into one object (was 7-9 positional args).
- Dedupe the 'last group reloads' ternary; type gesture options as
CommitMutationOptions; drop a Map+array wrapper around a single write.
* feat(studio): atomic z-order reorder via batch patch-element endpoint
Z-order reorder issued N per-element inline-style patches (one server
write each), so a mid-chain failure could leave a partial reorder on disk.
Add a patch-elements-batch endpoint that validates every patch, folds them
over the file in one in-memory rewrite, and writes once (all-or-nothing;
unsafe input rejects with no write). The reorder now sends one batch per
source file and records one undo entry. Because a failed atomic write
persists nothing, the interim disk-write-back rollback (restoreReorderedFile
/ restoreFulfilledReorderFiles / ReorderRollbackDeps) is deleted — failure
rolls back only live DOM/store state. Closes the last disk-atomicity gap.
* fix(studio): razor-split undo no longer silently no-ops
The split clone was written to disk without a data-hf-id, so the split
endpoint recorded that unstamped HTML as the undo entry's afterHash. The
next reloadPreview() ran the preview route's ensureHfIds write-back, which
minted a fresh id and persisted DIFFERENT bytes — so at undo time the disk
hash no longer matched afterHash and editHistory's content-mismatch guard
silently refused the undo (no write, no network, no error). Stamp the split
output via ensureHfIds in splitElementInHtml before it is written/returned,
so the preview write-back is a no-op and the recorded afterHash always
equals the final on-disk bytes. Fixes at the source rather than relaxing the
mismatch guard. Corrects the stale comment that credited forceReloadSdkSession.
* feat(studio): closed-hand grab cursor on the rotate handle
The rotate handle used the default arrow cursor; show a grabbing
(closed-hand) cursor on hover to signal it's grabbed and dragged to rotate.
* fix(studio): dropping a dragged element over another no longer selects it
A moved drag's release fired the box click, which re-selected whatever now
sat under the pointer via the hover cache — so dropping an element over a
higher-z one selected the drop target instead of keeping the dragged
element selected. The drag-move branch now suppresses the next box click,
mirroring the resize branch.
* fix(studio): group drag is one undo entry, not one per element
Dragging a multi-selected group committed each member's position write as
its own undo entry, so reverting took N Cmd+Z presses. Force a shared
coalesceKey (infinite window) across every member's commit so they fold
into a single undo entry, like the other multi-step commit paths.
* fix(studio): undo of a split no longer leaves a ghost clip in the timeline
The file and the composition iframe revert correctly on undo, but the
timeline panel kept a ghost node for the split clone. The element-merge
that repopulates the timeline preserves elements the fresh scan dropped —
intended for enriched sub-composition children a bare DOM re-scan misses,
but it also preserved a genuinely-removed TOP-LEVEL element (the split
clone after undo), leaving a phantom clip. Restrict the preserve to
elements with a compositionSrc (the enriched sub-comp children); a
top-level element missing from the fresh scan was truly removed.
---------
Co-authored-by: ukimsanov <ular.kimsanov@heygen.com>
What: the studio-server files route at its final NLE-stack form, with its
test suite (25 tests).
Why: standalone package seam — the server-side dependency of the studio
asset workflow, reviewable in isolation.
How: additive route behavior; existing route consumers unchanged.
Test plan: bunx vitest run src/routes/files.test.ts in packages/studio-server;
tsc --noEmit in packages/studio-server; fallow audit clean.
Ninth PR of the template-variables stack: the promote-a-property gesture.
Select an element on the canvas/timeline, open the Variables tab, and the
panel offers per-property bind actions.
- "Bind selected" card in the Variables panel, built from the selection:
image/media source (img/video/audio), text, text color, background, and
font. Each action declares a variable whose default is the element's
CURRENT value (promoting never changes the render — computed rgb colors
convert to hex, the first computed font family becomes the font default)
and writes the declarative binding the runtime resolves: data-var-src /
data-var-text attributes or `<prop>: var(--id)` styles. Declare + bind
run as one batched schema edit (one undo step); binding to an
already-declared id skips the declare and just binds.
- guarded to selections from the composition the session models — a
selection in another source file never writes bindings into this one.
- core: extract readVariablesForElement into runtime/variableScope.ts,
shared by color grading and the declarative bindings (was duplicated).
- fix(studio-server): buildSubCompositionHtml's extractElementAttrs
rebuilt html/body attributes without HTML-escaping values, shredding
quote-bearing attributes — data-composition-variables (a JSON array)
came out as mangled bogus attributes, so getVariables() silently
returned {} on every /preview/comp/* page (no declared defaults, no
runtime bindings). Pre-existing bug surfaced by live-testing this
feature; regression test added.
Verified end-to-end in a live session: select headline → Bind text color
→ declaration + var(--headline-color) written to disk → override in the
panel → runtime applies the custom prop and the element renders the
override.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Fourth PR of the template-variables Studio stack — the HTTP plumbing.
- preview routes (/preview and /preview/comp/*) accept
?variables=<url-encoded json> and inject
`window.__hfVariables = {...}` into <head>, before the runtime and any
composition script — the exact global the engine sets via
evaluateOnNewDocument at render time, so preview-with-values cannot
diverge from render output. Values are escaped against </script>
breakout, malformed payloads 400 instead of silently previewing
defaults, and the ETag is salted with a hash of the payload so cached
previews revalidate when values change.
- POST /projects/:id/render accepts variables ({variableId: value}) and
forwards them through StudioApiAdapter.startRender into the producer's
RenderConfig.variables — the same channel `hyperframes render
--variables` uses. Wired in both adapters (CLI embedded server + vite
dev adapter).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Documents the shared-pattern context (3rd copy of "resolve relative
data-start", after runtime startResolver.ts and the SDK's own
getElementTimings) and explains when the raw parseFloat fallback in
resolveStart's else branch can actually fire (a malformed grammar string
with a leading number). Adds a test pinning the "reference target exists
but its own timing is unresolvable" branch, which existing tests didn't
cover (only "target doesn't exist" was tested).
Cross-checked the negative-offset clamp concern raised in review: the
SDK's own resolveReferenceStart (session.ts) also clamps to
Math.max(0, ...), so this stays consistent with its sibling — no code
change needed there.
Same bug class as the SDK's getElementTimings fix (#2092): data-start can be a
relative-reference expression ("intro", "intro + 2"), not just an absolute
number. The old code did a raw parseFloat on it, so any reference silently
resolved to undefined instead of an actual time.
Also: this function never read data-duration at all (only data-start/data-end
literally), so a reference to a duration-authored (not end-authored) clip was
unresolvable regardless of the parseFloat bug — resolving a reference needs
the target's END, which for a duration-authored clip requires start+duration.
Both fixed together via the shared parseStartExpression grammar parser
(@hyperframes/core/runtime/start-expression), with the same cycle-guard
pattern as the SDK fix. Reference resolution against other elements is scoped
to this file's existing findById (bare data-hf-id lookup).
6 new tests: duration-based end resolution, relative reference (with and
without offset), missing target, and a mutual-cycle termination check.
Extending a clip past the video end used to force the server-fallback
path that fully remounts the preview iframe (the SDK fast path can't
express the root composition's data-duration, and the runtime bakes+drops
data-duration at load so it can't be patched live). On a large comp that
remount is a visible hitch.
Add a runtime control-bridge action set-root-duration -> clock.setDuration,
so the studio can grow the transport length in place. On an extend the
studio now posts it (and patches the clip's own timing live) instead of
reloading; it only reloads when a GSAP source rewrite actually happened
(the gsap-mutation endpoints now report a mutated flag). Non-animated
extends — the common case — commit as fast as a normal edit.
Verified: bridge dispatch + studio no-reload/post-message paths unit-
tested; core/studio/studio-server typecheck + suites green; the built
runtime artifact carries the handler; E2E confirms the extend no longer
remounts the preview and still persists.
Timeline UI
- Highlight clips visible at the playhead in the primary color; others share one neutral color
- Minimalist rounded clips, single-color track rows, no gutter icons or superscript labels
- Per-track eye toggle and a per-element hide button in the design panel
- Ruler zoom fixes: sub-second tick intervals and correct label formatting at high zoom
- Sticky gutter so track controls stay visible while scrolling
WYSIWYG visibility (data-hidden)
- Runtime honors data-hidden (display:none), so hiding affects the render, not just the preview
- HTML stays the source of truth; hide state persists and round-trips on reload
Split several studio files to stay under the 600-line cap; pure relocations, no behavior change.
* fix(parsers,sdk,studio-server,studio): unify hf-id space across preview, disk, and SDK session
Root-causes the setTiming element_not_found resolver-shadow divergence class:
timeline edits carry hf-ids read from the live preview DOM, but the preview
minted ids AFTER rewriting attributes (and never persisted them for sub-comps),
while the SDK session mints from the raw file — content-keyed minting then
yields different ids for the same element. Template-based comps were worse:
the SDK excluded the whole <template> subtree, so the session had zero
elements and every edit diverged.
- parsers: ensureHfIds now descends into <template> subtrees (linkedom's
querySelectorAll does not), minting and pinning inner ids
- sdk: buildRoots/buildElement treat <template> as a transparent container,
and resolution (resolveScoped, animation-id map) searches template subtrees
via querySelectorAllDeep — template comps now model, resolve, and edit
- studio-server: the sub-comp preview route persists hf-ids to the raw file
BEFORE the rewrite pipeline (mirrors the main route), pinning one id space
across served DOM, disk, and SDK session
- studio: resolver-shadow skips structurally-empty sessions (no event, no
attempt) and tags fail-open emissions with sourceReadFailed so read errors
are distinguishable from unwired readers in telemetry
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* fix(parsers,sdk,studio-server,studio): scope template descent, guard persist route
Addresses the 10 verified findings from the PR #1981 review:
- Restrict template transparency to COMPOSITION templates
(<template data-composition-id>) everywhere — ensureHfIds, SDK
buildChildren, querySelectorAllDeep. A plain <template> (runtime
clone-source) keeps its old fully-excluded behavior: stamping its
interior would duplicate one persisted id across every runtime clone,
and modeling it would show phantom timeline clips.
- Guard the sub-comp persist: only .html files (the wildcard route can
serve any project path — stamping an SVG corrupted it on disk),
try/catch the read (file-removed race becomes 404, not 500), salt the
etag (v2) so pre-fix cached clients don't 304 past the id pin, and
thread the stamped content into buildSubCompositionHtml so served ids
match the mint even when the disk write is skipped.
- Rewrite querySelectorAllDeep as a document-order DOM walk — appending
template matches after top-level matches made duplicate-id tiebreaks
disagree with the preview's unwrapped DOM (wrong-element edits).
- Recurse sourceMutation.querySelectorAllWithTemplates so server-side
ops resolve ids at any template depth, matching SDK resolution.
- Replace the empty-session silent skip with ONE tagged session_empty
event per session — silence would blind the tripwire to exactly the
modeling-gap class that exposed the template bug. Attempts stay
uncounted (an unmodelable comp can't cut over).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* fix(studio-server): close TOCTOU in sub-comp hf-id persist (CodeQL js/file-system-race)
Replace the route-level stat/read/persist sequence with stampFileHfIds:
validation (fstat), read, mint, and write-back all go through ONE open
file descriptor (O_NOFOLLOW where supported), so the path cannot be
swapped between validation and write. Falls back to read-only stamping
when the file isn't writable — content-keyed minting means the SDK
derives the same ids from the same bytes even without the disk write.
Addresses miguel-heygen's blocking review on PR #1981.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* fix(studio-server): linear-time template-attr match (CodeQL js/polynomial-redos)
promoteTemplateCompositionId's single-pattern regex backtracked
polynomially on crafted input. Two-step match: grab each <template>
open tag linearly, then find data-composition-id within that short
tag text. Same semantics (first template carrying the attr wins).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* test(studio): add design-panel QA fixture and triage matrix
Fixture project covering all panel-editable element archetypes,
plus the QA findings matrix from the design-panel bug campaign.
* fix(studio): make canvas selection hit intended elements
- honor author pointer-events:none in hit-testing (was selecting invisible overlays)
- pause playback before mousedown sampling; fall back to hover selection on null resolve
- invalidate committed selection when the active composition changes
- double-click keeps selection and defers to multi-candidate click cycling
* fix(studio): close remaining selection-layer review findings
- hoverSelection fallback now wired at all 3 mousedown call sites (box-click,
blocked-drag, plain overlay click) instead of just the overlay path
- pointer-events override detection reads computed style, not inline style,
so a CSS-class opt-in (not just inline style=) on a descendant is honored
- defensively remove the pointer-events override before the group-fallback
check too, closing a theoretical gap in the no-elementsFromPoint branch
- a click that resolves to nothing (dead-zone / deselect) no longer leaves
playback paused if it was already playing
* fix(studio-server): child-scoped patch operations with batch abort
- PatchOperation gains optional childSelector/childIndex resolved under the matched parent
- pre-pass resolves every op target; any miss aborts the batch with matched:false, no partial write
- style-decl parsing extracted to sourceStyleMutation to stay under the file-size cap
- new ./source-mutation subpath export (mirrors ./finite-mutation)