mathiasandClaude Opus 4.8
beeb5bc31b
A user waiting on a Summarize click shared the per-IP caption gate equally with the background firehose, so on a busy IP the click was slow or 429'd. Add a context-marked priority lane: the web path (engineProcessor.ProcessVideo) marks its context foreground; the gate serves foreground immediately while background fetches yield until no foreground is pending. Threaded via a context value (no new signatures) + a process-wide foregroundPending counter. Clicks are rare, so the background barely loses throughput; the waiting human gets the cleaner slot. Drops the credentials probe: ADR-010 and captions.go already settle it — the timedtext/InnerTube path rejects authenticated requests and the OAuth token does not authenticate it anyway, so auth cannot help and can hurt. Documented in ADR-026 rather than built. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>