The `subtitles` filter in ffmpeg requires libass at build time. The
homebrew `ffmpeg` bottle for 8.1 on arm64_tahoe is built without
libass — its configure flags have no `--enable-libass` and
`ffmpeg -filters` shows no `subtitles` filter at all. Every
`burnLiveTranscriptSubtitles()` call today hit:

    [AVFilterGraph] No option name near '.../subtitle.srt'

because the parser was treating `subtitles` as an unknown option name,
not as a filter.

### Fix

Use the keg-only `ffmpeg-full` binary at
`/opt/homebrew/opt/ffmpeg-full/bin/ffmpeg` for the subtitle burn
specifically. ffmpeg-full bundles libass + libfreetype + fontconfig
+ 43 other deps that the narrow bottle skips. It's keg-only so it
doesn't symlink over the existing narrow `ffmpeg` — other call sites
(narration mux via videotoolbox, recording mux, etc.) keep using the
fast narrow bottle. Only the subtitle burn reaches for the full one.

### Fallback

If ffmpeg-full isn't installed, fall through to the narrow `/opt/homebrew/bin/ffmpeg`
call as before. This preserves behavior on machines that don't have
ffmpeg-full yet (MacBook, CI). The narrow call will fail loudly with
the same error as before — that's strictly no worse than today's
silent failure.

### Install (one-time, per-node)

    brew install ffmpeg-full  # ~500MB–1GB, 5–15 min, 46 deps

### Log delta

The success log line now includes which ffmpeg binary was used:

    [ScreenRecord] live transcript subtitles burned: /tmp/...-subtitled.mov (ffmpeg=/opt/homebrew/opt/ffmpeg-full/bin/ffmpeg)

so operators can confirm the full binary was picked up post-install.

### Stacks on

#355 (subtitled_pending false-positive gate). Same branch tree. Neither
PR alone is sufficient: #355 makes the flag accurate; this PR makes the
burn actually produce output.

### History

Four wrong theories chased before landing on this one:
1. wrong process (voice-agent vs conversation-server)
2. stale local main (git fetch vs git pull)
3. filter rejection (entries.length === 0 after aggressive filter)
4. comma escaping in force_style (tried multiple backslash counts, all failed)

Susan raised "is it a dependency issue?" early in the thread. Correct
call; I dismissed it twice before finally running `ffmpeg -filters |
grep subtitles` and getting zero matches.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

…#354

Each script reproduces the bug (before the fix) and verifies it's resolved
(after the fix). All POCs pass on current main.

- poc-pr353-open-file.sh (11/11) — 18s polling timeout in open_file
- poc-pr355-subtitled-pending.sh (9/9) — false positive subtitled_pending
- poc-pr332-team-tier-revert.sh (9/9) — team-tier -C /tmp broke codex
- poc-pr325-bodhi-dep.sh (7/7) — bodhi dep pointed at deleted repo
- poc-pr354-retention-sweep.sh — retention sweep for stale results

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Per owner's design directive: "The recording tool should return the
files and the default file to use. The caller should process the result
and report abnormality if any. Then open_file tool should be called with
filename."

Changes:

1. open_file: stripped recording-specific logic.
   - Requires `path` arg (get it from recording tool result).
   - `find_latest_recording: true` flag as explicit fallback — only
     called when model lost the path, not as silent default.
   - Removed: subtitled_pending flag, version detection, polling
     logic, findRecording() as default behavior.
   - Kept: known file aliases (diagnostics), QuickTime activation,
     playback-path write, duration/size metadata.

2. screen_record stop: returns explicit file list.
   - New `files` object: `{raw, narrated, subtitled, recommended}`.
   - `instruction` string tells the model exactly which path to pass
     to open_file and how to offer alternatives to the user.
   - Subtitle burn still happens synchronously on stop.

3. No changes to record_screen_with_narration — its auto-stop timer
   fires in a setTimeout and can't return files to the model through
   a tool result. The model already has the raw path from the start
   call; open_file with that path works. Full file-list return for
   record_screen_with_narration is a follow-up.

Net: +39/-38 (near-zero). This is a separation of concerns, not new
features. findRecording() and findFfmpegWithSubtitles() are preserved
as helpers; they just stop being called by default in open_file.

Supersedes the approach in #353 (non-blocking return + subtitled_pending)
and makes #355 (subtitled_pending gate) + #357 (ffmpeg-full path)
unnecessary as open_file changes — though #357's findFfmpegWithSubtitles
is still needed in the recording tool's burn path.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Per owner's design directive: "The recording tool should return the
files and the default file to use. The caller should process the result
and report abnormality if any. Then open_file tool should be called with
filename."

Changes:

1. open_file: stripped recording-specific logic.
   - Requires `path` arg (get it from recording tool result).
   - `find_latest_recording: true` flag as explicit fallback — only
     called when model lost the path, not as silent default.
   - Removed: subtitled_pending flag, version detection, polling
     logic, findRecording() as default behavior.
   - Kept: known file aliases (diagnostics), QuickTime activation,
     playback-path write, duration/size metadata.

2. screen_record stop: returns explicit file list.
   - New `files` object: `{raw, narrated, subtitled, recommended}`.
   - `instruction` string tells the model exactly which path to pass
     to open_file and how to offer alternatives to the user.
   - Subtitle burn still happens synchronously on stop.

3. No changes to record_screen_with_narration — its auto-stop timer
   fires in a setTimeout and can't return files to the model through
   a tool result. The model already has the raw path from the start
   call; open_file with that path works. Full file-list return for
   record_screen_with_narration is a follow-up.

Net: +39/-38 (near-zero). This is a separation of concerns, not new
features. findRecording() and findFfmpegWithSubtitles() are preserved
as helpers; they just stop being called by default in open_file.

Supersedes the approach in #353 (non-blocking return + subtitled_pending)
and makes #355 (subtitled_pending gate) + #357 (ffmpeg-full path)
unnecessary as open_file changes — though #357's findFfmpegWithSubtitles
is still needed in the recording tool's burn path.

Co-authored-by: Chi <wangchi@Chis-Mac-mini.local>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>