fix(726): quote the decision record's rule: so PyYAML doesn't truncate it

`PR Gates / Script tests (pytest)` went red on
test_frontmatter_reader_matches_pyyaml_on_every_real_record. The rule: value was
an unquoted YAML plain scalar containing " #350's exclusion", and an unquoted
" #" starts a YAML comment -- PyYAML truncated the whole rule at "(mirroring",
so the catalog row and the mirrored MemPalace drawer carried half a sentence.

The hand-rolled frontmatter reader used by scripts/decisions_validate.py does NOT
tokenize comments, so it read the full line and reported OK; only the script-tests
job, which cross-checks the two parsers against every real record, can see this
class of defect. That is exactly what it exists for.

Fixed by single-quoting the scalar (doubling the internal apostrophe in
"image''s") and dropping the possessive from "#350's exclusion" so the token is
plain "#350". Verified both ways: PyYAML now returns the full sentence ending
"...race ahead.", and reverting the quoting reproduces the red, so the fix is
what makes the test pass rather than the test being insensitive.

Follow-up commit rather than an amend -- 56afa4652 is already pushed.

Refs #726

Decisions-Edit: yes
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/decisions/README.md

@@ -83,7 +83,7 @@ the link for rationale. Superseded/retired history lives in `archive/`. Regenera
 | `ffmpeg.qsv-decode-encode-split` | QSV decode is decoupled from QSV encode via a single `FFmpegProfile.QsvPreferNativeDecoder` bool (default ON, Linux-only), so a QSV encode profile can decode with the more tolerant native VA-API decoder instead of the QSV decoder, mirroring Jellyfin's hybrid decode/encode toggle instead of a general decode-family enum. | 2026-07-20 | [link](records/ffmpeg/qsv-decode-encode-split.md) |
 | `ffmpeg.qsv-extra-hw-frames-floor` | a QSV upload never emits `extra_hw_frames` below `FFmpegState.MinimumQsvExtraHardwareFrames` (64); a stored `0` or negative value is treated as "no pool configured" rather than honored literally, because with no headroom any unthrottled read exhausts the pool and the transcode writes nothing at all. | 2026-07-21 | [link](records/ffmpeg/qsv-extra-hw-frames-floor.md) |
 | `ffmpeg.qsv-hdr-tonemap-opencl` | the QSV pipeline never emits `vpp_qsv=tonemap=1`, which is a SILENT no-op on pre-Gen11 Intel graphics; HDR is tonemapped on the GPU via `hwupload=derive_device=vaapi` → `scale_vaapi` → `hwmap=derive_device=opencl` → `tonemap_opencl` when a VA-API device exists, the frames are still in software, and `tonemap_opencl` is available, and by the software `TonemapFilter` otherwise. The scale runs BEFORE the tonemap, and any hardware filter on the path forces the output to be re-tagged bt709. | 2026-07-26 | [link](records/ffmpeg/qsv-hdr-tonemap-opencl.md) |
-| `ffmpeg.readrate-catchup-sparse-streams` | a realtime video/audio input also gets `-readrate_catchup` (6.0) when the binary supports it — but NOT a still-image input (mirroring #350's exclusion) and NOT a concat input, which keep at most bare `-readrate` (a still image's video input takes none at all). Reason: `-readrate` paces the whole input off its furthest-behind stream, so a sparse stream sharing that input (an embedded PGS/DVD bitmap subtitle feeding the overlay) otherwise pins output at ~0.53x realtime. Catchup is a ceiling that applies only WHILE an input is behind, never a target, so it does not let a caught-up input race ahead. | 2026-08-04 | [link](records/ffmpeg/readrate-catchup-sparse-streams.md) |
+| `ffmpeg.readrate-catchup-sparse-streams` | a realtime video/audio input also gets `-readrate_catchup` (6.0) when the binary supports it — but NOT a still-image input (mirroring the #350 exclusion) and NOT a concat input, which keep at most bare `-readrate` (a still image's video input takes none at all). Reason: `-readrate` paces the whole input off its furthest-behind stream, so a sparse stream sharing that input (an embedded PGS/DVD bitmap subtitle feeding the overlay) otherwise pins output at ~0.53x realtime. Catchup is a ceiling that applies only WHILE an input is behind, never a target, so it does not let a caught-up input race ahead. | 2026-08-04 | [link](records/ffmpeg/readrate-catchup-sparse-streams.md) |
 | `ffmpeg.remote-image-fetcher-bounded` | remote graphics-engine images are fetched through `IRemoteImageFetcher` with a pooled `HttpClientFactory` client, a body-covering deadline, a wire-transfer size cap, and a decoder-enforced `DecoderOptions.MaxFrames` bound re-verified post-decode — never cached, re-fetched per element init. | 2026-07-20 | [link](records/ffmpeg/remote-image-fetcher-bounded.md) |
 | `ffmpeg.watermark-resolution-unified` | Every watermark `WatermarkSelector` resolves goes through one shared `ResolveWatermark` — the playout-item, channel and global precedence levels AND the deco path, for all three `ChannelWatermarkImageSource` values. An unresolvable watermark (missing file, un-migrated external URL, or no logo artwork) resolves to no on-screen bug plus a warning, never a dead path or a URL handed downstream; the one deliberate exception is a playout-item `Custom` with a blank image, which still falls THROUGH to channel/global. The generated-initials fallback is therefore off everywhere, including the deco path where it demonstrably rendered. Watermarks built OUTSIDE the selector (the song-progress overlay, #653) are not covered and remain unchecked. | 2026-07-26 | [link](records/ffmpeg/watermark-resolution-unified.md) |
 | `ffmpeg.work-ahead-slot-atomic` | `workAheadSegmenterLimit` is enforced by a single compare-exchange claim on a shared `WorkAheadSlots` pool taken by the *caller* of `Transcode`, which then passes ownership in and gets the release in `Transcode`'s `finally` — never a `Volatile.Read` compare in one place and an `Interlocked.Increment` in another. | 2026-07-21 | [link](records/ffmpeg/work-ahead-slot-atomic.md) |

docs/decisions/records/ffmpeg/readrate-catchup-sparse-streams.md

@@ -5,7 +5,7 @@ status: active
 since: '2026-08-04'
 supersedes: none
 superseded-by: none
-rule: a realtime video/audio input also gets `-readrate_catchup` (6.0) when the binary supports it — but NOT a still-image input (mirroring #350's exclusion) and NOT a concat input, which keep at most bare `-readrate` (a still image's video input takes none at all). Reason: `-readrate` paces the whole input off its furthest-behind stream, so a sparse stream sharing that input (an embedded PGS/DVD bitmap subtitle feeding the overlay) otherwise pins output at ~0.53x realtime. Catchup is a ceiling that applies only WHILE an input is behind, never a target, so it does not let a caught-up input race ahead.
+rule: 'a realtime video/audio input also gets `-readrate_catchup` (6.0) when the binary supports it — but NOT a still-image input (mirroring the #350 exclusion) and NOT a concat input, which keep at most bare `-readrate` (a still image''s video input takes none at all). Reason: `-readrate` paces the whole input off its furthest-behind stream, so a sparse stream sharing that input (an embedded PGS/DVD bitmap subtitle feeding the overlay) otherwise pins output at ~0.53x realtime. Catchup is a ceiling that applies only WHILE an input is behind, never a target, so it does not let a caught-up input race ahead.'
 signals: 'readrate, readrate_catchup, sparse stream, bitmap subtitle, PGS, DVD subtitle, dvdsub, pgssub, overlay burn-in, Live TV buffering/stalling, "Resumed reading at pts N with rate R after a lag of Ns" · paths: `PipelineBuilderBase.SetRealtimeInput`, `ReadrateInputOption`, `FFmpegKnownOption` · issues: #726, #350, #529'
 mechanics: '`PipelineBuilderBase.CatchupReadRate` (6.0); `ReadrateInputOption` catchup arg; `FFmpegKnownOption.ReadrateCatchup` capability gate'
 ---