* perf(studio): stop the manual-edit reapply loop from running while paused
* fix(studio): judge nested timelines by their parent, not the player alone
* fix(studio): bound the paused-ancestor walk and ignore unknown parents
* style(studio): format the manual-edit tests
* fix(studio): timeline clips keep their pictures while you scroll
With row virtualization on, the timeline dropped every clip's picture for the length of a scroll
gesture and put it back 100ms after the gesture stopped, so a zoomed-in timeline showed grey boxes
the whole time a person was moving through it. Clip content now stays mounted while scrolling;
pictures already loaded come straight from the thumbnail cache.
* perf(studio): clips that scroll into view get their pictures when the scroll stops
Keeping every clip's content mounted through a scroll made each jump of the 50,000-clip viewport
gate mount and lay out a screenful of new thumbnails, a 90 to 130 ms long task per run where main
has none. A clip's content now mounts only while the timeline is at rest and then stays through
later scrolls, so a picture already on screen never blanks and a scroll never mounts new ones.
* perf(studio): refresh only the edited scene's thumbnails and let the preview load first
One scene edit regenerated every sidebar and timeline thumbnail, and those renders starved the new preview's requests on the Studio server. The thumbnail cache now keys on what a composition renders from, the server names the compositions a write affects, only those thumbnails refresh, and composition thumbnails wait while a shadow preview reload is in flight.
* test(studio): pin scene-scoped thumbnail reuse and the preview-reload hold
Memoizes the scoped thumbnail signature on the project signature so requests keep reusing the adapter's cached one, keeps the fresh-signature check that catches a write the watcher has not reported yet, and adds tests for sibling-scene reuse, root-head invalidation, the affected-composition set, per-path revisions and the scheduler hold.
* refactor(studio): share the file-change payload guard
* fix(studio): match thumbnail revisions for scenes mounted with a ./ path
* perf(studio): keep signature cache keys constant-size
* style(studio): format thumbnail-scope changes
* docs(studio): trim thumbnail input comments
Every timeline render re-sorted every clip in the project once per visible row to find transition
seams, then kept the row's own. On the 50,000-clip viewport fixture that sort was the largest CPU
cost in a scroll. Seams are now derived once per change of the clip set, grouped by track, and each
row looks up its own. Pairing within a track also fixes a missing transition badge when a clip on
another track starts between the transition's two clips.
Two residuals from the cutover-dashboard work, both found in the data the
first pass shipped (0.8.61/0.8.62).
`absent_or_empty` was one label over two different failures: the route
answers `content: ""` both from the `optional=1` shim (nothing resolved at
that path) and for a real 0-byte file. The route now marks the shim with
`missing: true`, and the read path with `missing: false` so the field's
PRESENCE is what tells the client this server draws the distinction — a new
server's empty file would otherwise look exactly like either case from an
old one. Client splits them into `absent` and `empty_file`; a server without
the field still reports `absent_or_empty`, so the existing series stays
honest instead of silently folding into one of the new ones.
Why it is worth splitting: on 0.8.62, 75 tabs hit this class and not one of
them ever landed an SDK edit afterwards — it is terminal for the tab, while
the tab keeps playing back and navigating, so nothing surfaces to the user.
Every measured case with a loaded tree carries `path_in_tree: true`: a file
the tree lists and this read cannot get. Which of the two causes that is
decides the fix, and until now the event could not say.
`res.json()` at the end of the read was unguarded, so a 200 carrying HTML —
an SPA fallback or a proxy answering in the route's place — rejected out of
the function entirely and the effect's outer catch filed it as
`stage: "open"`, which asserts the COMPOSITION failed to parse. Observed in
production on 0.8.62: `Unexpected token '<', "<!-- /*!"... is not valid
JSON`. That is the third label to make the same wrong claim, after the
fetch-rejection split in #4240 and #4269. Now `reason: "invalid_json"` with
the response's content-type.
`path_in_tree` now rides all three empty-read reasons, not just the combined
one, so the split keeps the signal that justified it.
Tests: 4 new (absent / empty_file / combined-label fallback / non-JSON 200)
plus a server test pinning `missing` on both answers. 1172 tests green
across studio hooks + studio-server routes; oxlint, oxfmt, tsc clean.
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
* fix(studio): composition and text clips show their frame at full strength
CompositionThumbnail drew its frames at 0.7 opacity with a lighten blend, the only timeline
picture dimmed that way; on a light theme the frame nearly vanished into the clip. Opacity and
blend are now theme tokens, untinted by default like video and image clips.
* fix(studio): touching clips show a hairline seam where they meet
Two clips that meet end to start used to read as one long bar. Each exact join on a row now
gets a 1px line in the row colour, drawn over the clips. Clip positions, widths and keyframe
diamonds do not move, so the timeline still tells the truth about time.
* fix(studio): hide clip join seams while a clip is being moved
A moved clip is drawn by the drag overlay, not at its element position, so its join line stayed
behind at the old boundary until the drop. Rows draw no join lines during a move or multi-clip
drag; they come back on drop. The join math now reuses the lane helpers for sort order and the
touching tolerance.
* refactor(studio): drop a multi-drag check the move-drag check already covers
A multi-clip drag preview only exists once a move drag has started, so the join lines only need
the move-drag check.
@hyperframes/studio's public index doesn't export the clip-content
thumbnail primitives, forcing a deep import. Desktop's Canva timeline
lane needs to draw audio waveforms and image thumbnails from a host
app without reaching into the package's internals.
Adds a test that mounts each export through the package name the way
a host app would (not a relative import), so a future removal or
accidental un-export fails a test instead of a downstream deep-import
workaround.
* refactor(studio): keep legacy fixture state out of rendered rows
* fix(studio): keep timeline keyboard actor mounted
* refactor(studio): remove expansion telemetry and prove stable nested rows
* test(studio): type nested timeline fixture broadly
* test(studio): remove expansion lane assertions
* test(studio): assert nested row identity by key
* fix(studio): satisfy removal and format guards
* fix(studio): clear fallow findings in timeline cleanup
* test(studio): update timeline removal expectations
* fix(studio): remove stale timeline test helpers
* fix(studio): keep automation lanes mounted without disclosure
* refactor(studio): keep audio lanes while removing clip expansion
* fix(studio): restore audio disclosure state
* test(studio): remove obsolete expanded fixture assertions
* fix(studio): resolve provider rebase without clip auto expansion
* fix(studio): remove inline keyframe expansion rows
* fix(studio): restore automation disclosure state
* fix(studio): remove stale timeline model inputs
* fix(studio): pass animation state to timeline layout
* fix(studio): remove stale expansion tests and helpers
* test(studio): cover shared audio lane labels
* fix(studio): remove unused keyframe callback plumbing
* fix(studio): clear rebase lint leftovers
* fix(studio): remove unused timeline header export
* style(studio): format timeline cleanup
* fix(studio): restore composable timeline exports
* fix(studio): keep audio lanes open across selection
* fix(studio): align timeline lane test contract
* fix(studio): remove stale lane test import
* fix(studio): align track header test callback
* fix(studio): remove stale track header test prop
* test(studio): preserve ruler half pixel alignment
* test(studio): keep audio lane fixtures drawable
* test(studio): assert shared lane owner label
* fix(studio): align audio lane expansion with layout state
* test(studio): use the audio lane owner label
* fix(studio): unify audio lane expansion state
* fix(studio): align automation lane labels
* fix(studio): remove stale lane height import
* test(studio): assert automation labels against the real curve, not a formula
The previous test recomputed the expected top with the same formula
the fix uses, so a regression in TimelineAutomationLaneSlot's own
offset would still read green. Moved it to TimelineLanes.test.tsx,
which mounts both the header and the canvas, and compares their
rendered [data-automation-lane-label]/[data-automation-lane] tops
directly.
* revert(studio): restore the keyframe-row feature from main
Miguel: keep the per-property keyframe rows (diamonds, prev/next
arrows, disclosure, auto-open) exactly as main. This PR's real scope
is removing dead expandedParentStart consumers, not the keyframe-row
UX.
* refactor(studio): remove dead expanded-child timeline code
expandedParentStart is never set anywhere on main (the inline
sub-composition child-row expansion that produced it was already
removed in #4132/7797c5ead). Delete its now-dead consumers: the
TimelinePane move/resize/delete/split rebase wrappers, the ZMirror
call site that routed through them, the timelineDragLanding topology
guards, isMainTrackElement's expanded-child exclusion, laneGapFloor's
host-window-start math, and the paired expanded-clip-edit telemetry.
Keeps every keyframe-row feature (diamonds, prev/next arrows,
disclosure, auto-open, telemetry) untouched.
The error handler called cleanup(), which sets video.src = "" and calls
load(). Clearing src itself fires another error event, re-entering the
handler at event-loop speed — every pass allocating a React update via
setFailed(true). The seeked path triggers the same loop: its cleanup
provokes the synthetic error right after a successful frame extract.
Detach the error listener inside cleanup() and ignore the synthetic
empty-src error. Instrumentation on a real session measured ~475k src
assignments/second and ~8.6 MB/s of update allocations before the fix.
Fixes#4036
Co-authored-by: CasbaL <26603379+CasbaL@users.noreply.github.com>
The shadow reload promotes on frame-driven readiness (the player's
paint-and-idle, then two requestAnimationFrames) but failed on a
wall-clock 15s setTimeout. A hidden tab renders no frames, so every
external edit made while Studio was in the background failed with
"it took too long to load", the toasts stacked, and the stale preview
stayed up even after returning to the tab.
The budget now only runs while the document is visible: hiding the tab
clears the timer, and showing it again restarts the full budget for the
pending shadow, which then promotes normally.
Fixes#4290
— Rames Jusso
Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
* feat(studio): render geometry-sized video filmstrips
* fix(studio): keep poster tier during timeline scroll
* fix(studio): cap rendered thumbnail tiles
* chore(studio): refresh filmstrip checks
* chore(studio): refresh filmstrip captures
* chore(studio): refresh four-times captures
* fix(studio): stop capping filmstrip render tiles at 33
computeThumbnailStrip no longer clamps frameCount; the decode-side cap already lives in quantizeThumbnailFrameCount. VideoThumbnail only acquires the rich filmstrip lease when requestFrameCount > 1, so a narrow clip issues one decode job instead of two identical ones. Deletes the unreachable duplicate defaults in createVideoThumbnailRequest.
* style(studio): format filmstrip changes
Implements the fixes from the 2026-09-21 cutover dashboard read
(plans/sdk/2026-09-21-cutover-dashboard-fixes-plan.md):
- sdk_cutover_failed now carries `family` and `error_kind`
(network/conflict/http/sdk). The one production gate event was a raw
`TypeError: Failed to fetch` from an unwrapped fetch (readProjectFile /
writeProjectFile's preflight), which an instanceof-only classifier would
still file as "sdk" and trip the rollback gate — added a message-based
fallback for the browser's fetch-rejection strings.
- studio:sdk_session_unavailable's `network` reason now carries `elapsed_ms`
and `hidden` (document.visibilityState at rejection), separating a
near-instant policy block (CSP/PNA/extension) from a dropped connection
the tab or server going away mid-flight.
- The ownership-race branch in useSdkSession's open effect now emits
sdk_session_superseded instead of sdk_session_unavailable{stage:ownership}
— it's a benign race (identity moved on mid-open), not a broken
precondition, and was being counted as one on the dashboard.
- Root-caused and fixed the read-404 "storm": /api/events (CLI host) and
the vite-dev hot-reload channel are one connection per SERVER, not per
project. A stale tab left open after `hyperframes preview` restarts on a
different folder (same port) received every save the CURRENT project
made, reloading its preview (which then 404s) and re-reading its own
composition on each one. Both transports now carry `projectId`; the
client-side coordinator drops a delivery whose projectId doesn't match
the tab's (absent field still passes, for one release of skew).
- studio-server's file routes report `why` on 403/404: `project_dir_missing`
(new — the CLI host's static resolveProject kept answering for a project
whose folder was renamed/deleted under a running server, which used to
fail closed as an indistinguishable path-traversal 403) vs `nul` vs
`outside_project`.
- absent_or_empty reads now carry `path_in_tree` (against the caller's
loaded file tree). Instrumentation only, per the graveyard page
(clearing-activecomppath-on-tree-absence) that refuted the "clear
activeCompPath" fix this was the proposed next step for.
Tests: unit coverage added for every change (sdkCutover.test.ts,
useSdkSession.lifecycle.test.tsx, useExternalFileChangeCoordinator.test.tsx,
studioServer.test.ts, files.pathSafety.test.ts). oxlint/oxfmt clean,
tsc --noEmit clean on studio/studio-server/cli.
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
* feat(studio): timeline clips take the designed material
Picture clips use an 8px radius and audio clips a 21px pill.
Clips sit one step above the lane. The label is a chip that
drops under 60px. Selection keeps the inset outline plus a
1px inner highlight. Hover background is the only transition.
* style(studio): format timeline clip shadow
* fix(studio): restore handle-bar transition and de-pin box-shadow test
* feat(studio): menus and popovers paint instantly
Menus and popovers open and close with no fade. Hover colour is unchanged.
* fix(studio): fade menus in from a visible shape
Menus, popovers, and dropdowns start at opacity 0.8 and scale 0.97, then settle in 120ms. They close in 90ms. Tooltips use the same shape in 100ms.
* feat(studio): audio meter faders for groups and master
* fix(studio): meter's mid band uses amber-500, the theme's actual token
yellow-500 was reset to nothing by palette-reset.css (--color-*: initial)
and never redefined in theme.css, so the mask never revealed any color
for -6 to -3dB; the token gate test already catches this and was red.
* refactor(studio): rename YELLOW_AT to AMBER_AT to match the amber token
* fix(studio): fader nudge and aria-valuenow match the visual dB position
* refactor(studio): use core StereoLevel for meter channel shape
* fix(core): emit levelTap in the packed core build
* fix(studio): name the preview fader Monitor and share clampNumber
* fix(studio): split the meter rAF tick and cover its branches
* style(studio): oxfmt AudioMeterStrip tests
* fix(studio): preserve authored gain in audio meter faders
* fix(studio): make timeline audio meters opt-in
* feat(studio): typed audio values, clip fades, audible video drops
Audio rows in the media inspector (Volume, Speed, Media start) take a
typed value: click the readout, type "-6 dB", "1.5x" or "2.5s", Enter.
Speed presets are hidden on <audio> clips.
Clip-edge fades: data-fade-in / data-fade-out in seconds, honoured by the
preview runtime (per-tick gain), the render mixer (afade after volume) and
Studio (Fade in / Fade out rows, and drag dots at the top corners of audio
clips and audible videos). Linear on both sides so preview and render
agree; fades that outrun the clip scale to meet inside it.
Dropped videos with an audio stream now land with data-has-audio="true"
instead of muted, so the mixer keeps their sound. The media metadata
endpoint reports hasAudio from the ffprobe call it already makes.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
* fix(audio): one owner for fades, dB, and afade-after-volume
Illegal fade values become no-fade at fadeGain; typed inspector input
still returns null so the readout stays red. Master and group mixes
share one filter chain with volume then afade. Fade-out stays anchored
to the trimmed clip end.
* fix(studio): share audio helpers and bound typed media values
* fix(studio): reserve sibling fade duration when editing
---------
Co-authored-by: Jake Moran <jakemoran2011@gmail.com>
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
Co-authored-by: Miguel Angel Simon Sierra <miguel.sierra@heygen.com>
* feat(studio): audio level meters at the timeline's right edge
* test(core): cover metering started before the audio context finishes init
* fix(studio): keep meter follow after a dead preview and start bars at silence
* fix(studio): keep the 0 dB peak tick inside the meter
* fix(studio): keep the 0 dB peak tick visible without calc()
* fix(core): tap meters on the program bus, mute on a monitor gain
* style(core): wrap applyMasterGain to satisfy oxfmt
* fix(studio): report a rejected read as a network reason, not an open failure
`stage: "open"` is documented as `openComposition` threw — an unparseable
composition, or OOM. Every event in that bucket on 0.8.56 and 0.8.57 carries a
fetch-rejection message instead: "Failed to fetch" (28 users / 11 users), "Load
failed", "NetworkError when attempting to fetch resource.".
The cause is one missing catch. `readProjectFileOptional` awaits `fetch` with no
try/catch, so a rejected request escapes the function and is caught by the
effect's outer `.catch` — the handler written for `openComposition`. The read
path has a five-member reason union precisely so this class of failure is
diagnosable, and the one case that never produces a response was the case
outside it.
That made the largest SDK-session failure class in Studio (2.9% of session users
on 0.8.56, 2.3% on 0.8.57) unaddressable: you cannot fix a network failure while
it is reported as a composition that failed to parse.
Now `readProjectFileOptional` catches its own rejection and returns
`reason: "network"`, so it lands in `stage: read` with everything else, and
`stage: open` means only what its comment says.
Telemetry only. Nothing branches on the stage and no user-facing behaviour
changes. Fifth split of this shape, after `ineligible_operation` (v0.8.49),
`stage: read` (v0.8.51) and `block_detail` (#4214).
Co-Authored-By: Claude Code <noreply@anthropic.com>
* test(docs): point the catalog tab-row test at the page gutter #4238 moved the inset to
`catalog-detail.test.ts` asserted the exact strings that #4238 deleted:
`.hf-ve-tabs-row { margin: 20px 0 0 16px; }` and `.hf-ve-body { padding: 2rem 0 0 16px; }`.
That PR removed both insets deliberately — its own comment says "the page gutter is
the page's job, and a second 16px here put everything below the stage on a
different left edge from the title, install block and stage above it" — and
restored the gutter on `#content-area` in `docs/custom.css` instead. The test was
left asserting the old mechanism, so main has been red on it since, unnoticed
because the `Test` workflow does not run for a docs-only change.
The invariant did not change: this content is still inset from the page edge. Only
the mechanism did, so the test now asserts both halves of it — the two rules carry
no inset of their own, and the gutter standing in for them is still present, at both
its values. Asserting only the first would keep passing if the gutter were deleted
outright, which is the regression the test exists to catch; both mutations were
checked and both fail.
Co-Authored-By: Claude Code <noreply@anthropic.com>
---------
Co-authored-by: Claude Code <noreply@anthropic.com>
A tab whose project the running Studio cannot resolve failed every composition
read with a 404 and said nothing. `useSdkSession` recorded the failure to
telemetry and returned, so the editor looked normal while every edit silently
took the server path instead of the SDK — nothing landed, and nothing said
why. The `out-fb1` timeline sat in that state for an hour and a half, through
a reload that passed mount validation.
The banner names both sides: "This Studio is serving X. This tab was opened
for Y." That is the whole truth in the host that produces these 404s. The
CLI-embedded Studio serves exactly one project, and `hyperframes preview`
reuses port 3002 when the folder matches, so starting it on a different
folder takes the port out from under an open tab — and the project the old
tab was pointed at is untouched on disk. "No longer available" would be
false: nothing was lost, and the same timeline shows the project return.
With several projects served (the Vite host) a rename cannot be told from a
deletion, so that wording claims no cause.
`reportReadFailure` answers which project a failed read identifies. Only a 404
does; a 5xx, a dropped request, an unexpected body or an empty file say nothing
about which project the server serves, so none of them claim it.
Also fixes a smaller lie on the same path: `useFileTree` parsed the 404's JSON
body without checking `r.ok`, so the failure took the success branch and
recorded an empty tree — and an empty provenance snapshot for a project that
was never read — which then travelled out in bug reports.
The 404s continue; this ends the silent part, not the failure.
Co-authored-by: Claude Code <noreply@anthropic.com>
The mount path has validated its hash since v0.8.52. The hashchange path did
not — it adopted whatever id the URL offered, so changing projects walked
straight around the mount fix and re-armed the same failure: every later
/api/projects/<id>/... request 404s for the life of the tab, including the
composition read that opens the SDK session.
Same tri-state as mount: ok adopts, unknown adopts (a transient check failure
must not rewrite a hash that is probably fine), missing falls back.
Three details that are not obvious from the diff:
- **The race guard reads the hash, not a counter.** This effect re-registers on
every projectId change, so a `generation` in that closure resets and an
in-flight verdict from the previous registration would read as current —
adopting a project the user already navigated away from. The hash cannot go
stale, so it is the ground truth to compare against after the await.
- **The fallback re-fetches the project list.** tryConnect has `data.projects`
in scope; this path does not, and caching the mount value would be stale in
exactly the long-lived-tab case this exists for.
- **Both rewrites use replaceState.** `location.hash =` pushes, leaving the dead
id one Back away — and Back would then re-validate, fall back, and push again,
forever. The mount fallback had this bug too; fixed here as well.
Also emits the hashchange verdict so the `unknown` branch — which deliberately
keeps the hash and is invisible from outside — is countable.
Verified: 7 mutants, 7 caught, including adopting without validating, collapsing
unknown into missing, trusting the verdict over the live hash, memoizing the
fallback list, and pushing on either rewrite. Full studio suite 5,323 passed.
Co-authored-by: Claude Code <noreply@anthropic.com>
Two telemetry gaps, both pure instrumentation with no behaviour change.
`tab_id` — distinct_id identifies a browser, not a page. Several
investigations stalled on "two tabs, or one tab switching?", because a burst
of events alternating between two project hashes is indistinguishable from a
user moving between projects, and `session_start` fires once per page load so
counting it cannot tell them apart either. One id per page load, from one
shared module, attached by BOTH transports (`studio:*` and `studio_*`) — those
two families already drifted once on how `agent_runtime` is encoded.
Deliberately not persisted. Storage would survive a reload and quietly turn
this into a tab-session id, changing what every query means, and blocked or
cleared storage would make the property intermittently absent — which reads as
"old client" rather than "storage unavailable".
`project_hash_validated` — a tab that keeps its hash because the check itself
failed ("unknown") is currently indistinguishable in production from one that
never ran the check. Different causes, different fixes, one silent bucket.
Emits `stage` (mount | hashchange), `outcome` (ok | missing | unknown), and
the HTTP status when the server answered.
Verified: 8 mutants, 8 caught — including dropping tab_id from either
transport, regenerating it per read, persisting it to storage, emptying it in
the no-DOM fallback, and collapsing "unknown" into "missing". Full studio
suite 5,314 passed.
Co-authored-by: Claude Code <noreply@anthropic.com>
* fix(studio): reloading the preview swaps in a ready copy instead of blanking
* fix(player): report painted once assets are ready and the loader has faded out
assetsready fires when the loader fade starts, so a consumer promoting on it can
expose a raised or fading panel. painted fires once per document load after the
fade completes, with a getter for late listeners; it resets on each load.
* fix(studio): promote the shadow preview only when painted, under one wait budget
Studio waited for ready plus two frames, which can land while the player's loader
panel is still up or fading. It now also waits for the player's painted event.
The shadow no longer arms the 5s adapter give-up, so a slow but live load fails
only at the single 15s budget. Set-destination availability follows the live
iframe across a swap.
* feat(studio): edit a clip's speed ramp with a rate lane and presets
* fix(studio): keep the live preview attribute in sync with what gets persisted
* fix(cli): snapshot picks the source frame through a rate lane and up to 10x
hyperframes snapshot clamped the constant playback rate at 5 and ignored a
rate lane in data-automation, so a sped-up or ramped clip showed the wrong
frame. It now reads the rate through the runtime's own reader and maps time
with the shared source-time function.
* docs(skills): teach speed ramps as a rate lane in one reference page
Adds the speed-ramps reference, corrects the 0.1 to 5 rate range to 0.1 to 10
and the 'speed ramps are not supported' lines in the skills, and regenerates
the skills manifest.
* docs(skills): say what fixes a ramped clip's length and how the render approximates pitch
* fix(studio): hide the speed preset until the clip has a known duration
A preset on a clip with no data-duration was stretched over a made-up one
second. The panel now offers presets only when the duration is known.
* docs(skills): fix the last stale ramp line in the editing recipes and the slice-cap wording
* feat(studio): a host can make the preview read-only
Gates the shared geometry commit funnel (offset/size/rotation), so the
inspector's manual X/Y/W/H/rotation fields refuse the same as canvas
drag/resize/rotate. The flat inspector's fields render disabled with a
host-supplied reason. Fixes a hooks-order crash on deselect found in review.
* refactor(studio): derive the read-only preview flag from context, not a synced store
EditorShell synced its readOnlyPreview prop into a zustand store via a raw
useEffect behind an eslint-disable of no-restricted-syntax. Replace it with
a PreviewReadOnlyProvider context computed fresh from the prop every render:
Tier-1 consumers (genuine EditorShell descendants) read it via useContext;
Tier-2 consumers (useAppHotkeys, useGestureCommit, the
useDomEditSession/useDomEditCommits/useDomGeometryCommits chain), which run
in App.tsx above EditorShell, take it as an explicit parameter threaded from
StudioApp's own prop instead. Adds a host-mount test proving EditorShell
gates its descendants from its own prop with no StudioApp/App.tsx involved.
* fix(studio): keep preview hotkeys context explicit
* fix(studio): close read-only interaction escapes
* fix(studio): preserve timeline ownership in read-only preview
* fix(studio): rollback read-only preview work
* fix(studio): keep hotkey ownership on the active surface
* fix(studio): format preview overlay and strengthen split test
* fix(studio): clear preview gate findings
* refactor(studio): share preview test fixtures