## drawElement fast-capture — config + CLI flag (stack 1/6)
Foundation layer for the drawElement fast-capture feature: the config surface and CLI/Docker plumbing that the rest of the stack builds on.
### What this adds
- **`packages/engine/src/config.ts`** — new config fields for fast capture: `useDrawElement` / `enableDrawElementWorkerEncode` (macOS-GPU `drawElementImage` capture + worker-offloaded JPEG encode), resolved from env in `resolveConfig` (env `HF_DE_WORKER_ENCODE`). Wired alongside main's existing `staticFrameDedup` (unified downstream in 4/6).
- **`packages/cli/src/commands/render.ts`** — `--experimental-fast-capture` flag → sets `experimentalFastCapture`; `--debug` passthrough.
- **`packages/cli/src/utils/dockerRunArgs.ts`** — pass the fast-capture env through to the container.
- **`.github/workflows/fast-video-validation.yml`** — CI job validating fast-capture renders.
- `.oxlintrc.json` / `.fallowrc.jsonc` — ignore-pattern housekeeping for the new paths.
### Notes
- Config-only + entrypoint; no capture behavior yet (that's 2/6–4/6).
- Tests: `config.test.ts`, `dockerRunArgs.test.ts` added.
---
**Stack (drawElement fast-capture, rebased onto current `main`, supersedes #1295 + #1444):**
1. **#1916 config + CLI** ← you are here
2. #1917 drawElementImage capture service
3. #1918 3D projection + compositor-effect risk gate
4. #1919 frame-capture core (routing, worker-encode, static-dedup unification)
5. #1920 producer render stages + remote bg-image localizer
6. #1921 lint rule + player media sync
⚠️ Intermediate PRs (1–5) are split by package boundary for review and **do not each compile independently** (cross-file deps); the complete feature is green at the stack tip (#1921) — tsc-clean on engine + producer, 231 tests pass.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
The timing compiler scanned raw HTML with tag regexes that weren't
comment-aware, so a comment or script merely mentioning `<video>`/`<audio>`
was rewritten as a real element — injecting id/data-start/data-hf-auto-start
into the comment text. That phantom attribute then tripped the probe stage's
substring check (`html.includes("data-hf-auto-start")`), launching an
unnecessary browser probe on every render with an unexplained empty reasons list.
- Mask comments, <script>, and <style> regions before the tag scan, then
restore them verbatim (compileTimingAttrs, extractResolvedMedia).
- Replace the probe's substring match with a DOM query
(video[data-hf-auto-start]) and add "auto-start video(s)" to the reasons list.
* feat(lint): flag dir="rtl" on <html> as a confirmed silent render failure
Two independent reports diagnosed the same exact bug: dir="rtl" (or any
non-ltr value) on <html> renders correctly in preview/snapshot but
produces a fully blank/black video from render, with no other
lint/validate/inspect check catching it - output file size (far smaller
than expected) was the only tell for both reporters. Both independently
confirmed the same fix: drop dir from <html>, keep lang, and scope
direction: rtl to individual text-containing elements via CSS instead.
Could not empirically verify the render pipeline's own root cause in this
session (headless Chrome screenshot capture is unreliable in this
sandboxed environment - even a baseline, non-RTL capture timed out), so
this ships the safe, already-confirmed advisory rather than guessing at a
runtime fix. Both reporters explicitly asked for exactly this: "deserves
a lint rule or render-time warning."
* fix(lint): only flag valid non-ltr html dir values
* feat(cli): emit sign-in lifecycle telemetry
The CLI tracks command and render lifecycles but emits nothing for
`auth login`, so sign-in outcomes are invisible on the observability
dashboards — a completed sign-in, an abandoned browser flow, and a
rejected key all look identical (absent). This leaves a blind spot in
the same funnel the render events already cover.
Add three events mirroring the existing `trackX` pattern:
- auth_login_started (method: oauth | api_key)
- auth_login_completed (method)
- auth_login_failed (method, reason)
`reason` is a fixed low-cardinality enum (flow_error / no_credential /
rejected / invalid_input). No token, key, identity, email, or free text
is ever attached — consistent with the existing anonymous telemetry and
the `telemetry disable` opt-out. Wired into both the OAuth and
--api-key paths in `auth login`, with unit coverage for the new events.
* fix(cli): close sign-in telemetry funnel dropout gaps
Follow-up so `started` reconciles to `completed + failed` on the common
abandonment paths, which the first cut missed:
- Interactive prompt cancel (Ctrl-C) now surfaces as a throw that the
single catch in the api-key path records as `aborted`, instead of a
bare exit with no event.
- A stdin read that times out in non-TTY `--api-key` mode now records
`aborted` before the error propagates, rather than exiting silently.
- OAuth split: a timed-out browser callback (user closed the tab) is
tagged `flow_timeout`, separated from real `flow_error` (IdP/network),
since the walk-away timeout is the dominant non-error dropout.
Also pre-plumb an optional `distinctId` on the three trackers, mirroring
trackRenderComplete/trackRenderError. Unused today; it lets a later
identity-level attribution be a one-line callsite change rather than a
signature sweep. Coverage added for the new reasons and forwarding.
Vance Ingalls