**BUG-1 & BUG-2 — Wrong audio plays after re-render / MP3 doesn't match text**
Root cause: audio files were named by index (cue_0.mp3, cue_1.mp3). When a cue
was inserted or deleted, all following indices shifted but old MP3 files kept
their original names, so re-render would play the wrong audio for the wrong cue.
Fix: renamed files to cue_N_CONTENTHASH.mp3 and introduced an ad_cue_manifest
stored in the job document that maps each cue index to its correct GCS URI.
Re-render now reads from the manifest instead of guessing by filename.
Also: editing AD cue text in the VTT editor now automatically queues TTS
regeneration for changed cues — no more silent mismatches.
**BUG-3 — App crash / state desync when uploading VTT or clearing TTS queue**
Fixed handleVttFileUpload to only update local editor state after the server
confirms the save — previously local state was updated first, so a network
error left the UI showing content that wasn't actually saved.
Fixed handleClearRegenerationQueue to only remove items from local state if
the server removal succeeded — previously all items were cleared regardless.
**BUG-4 — AI generates different audio descriptions every time**
Added GenerateContentConfig(temperature=0.2, top_p=0.8, top_k=40) to the
Gemini API call so output is more consistent across runs.
**BUG-5 — On-screen text inconsistently described**
Strengthened the AI prompt rule from a vague suggestion to a mandatory
requirement with an explicit format: "Text on screen reads: [exact text]".
Applied to both gemini_ingestion.md and gemini_ingestion_targeted.md.
**BUG-6 — No notification when re-render finishes**
Added rendering_qc toast notification and a dismissible green banner that
appears in QCDetail when re-render transitions to pending_qc. The banner
auto-dismisses after 10 seconds. Also increased WebSocket reconnect attempts
from 5 to 15 and capped backoff at 60s to prevent falling back to manual refresh.
**BUG-7 — Timeline preview looks accurate but isn't after edits**
Added isStale prop to TimelinePreview. The timeline now shows an amber tint
and "Preview may be outdated" label whenever there are unsaved pause point
changes, pending TTS regenerations, or a new VTT has been uploaded.
**BUG-8 — ElevenLabs API errors break TTS with no fallback**
Added try/except fallback chain in _synthesize_single_cue: if the configured
provider fails, it automatically retries with google, then gemini.
**BUG-9 — Concurrent re-render requests cause race conditions**
Made the PENDING_QC → RENDERING_QC status transition conditional (only
succeeds if the job is still in PENDING_QC). Returns HTTP 409 if a re-render
is already in progress. The completion transition back to PENDING_QC is also
conditional so a cancelled/overridden render doesn't corrupt job state.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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