docs: plan ad11 reliability sweep follow-up

[KitsuneKode]

Summary

Adds an implementation plan to land the ad11 reliability PR stack safely and close the gaps/regressions identified in review.

Plan: .plans/2026-07-10-ad11-reliability-followup.md

Also indexes the track in .plans/plan-implementation-truth.md.

What the plan covers

Phase 0 — Integrate

• Merge order for the six unique cursor/*-ad11 branches
• Close duplicate ci-shared-test-stabilization-ad11
• Resolve shell-frame.tsx (overlay suspend + footer keybind gate) and SourceInventoryService conflicts

Phase 1 — P0 regressions

• Restore YouTube diagnostics probes on the unified overlay path
• Replace Object.defineProperty cancellationReason with an explicit live ref
• Emit playback.fallback.degraded when all alternates are down

Phase 2 — Hardening

• Pause browse calendar ticks under overlays
• Browse state preservation + screen-clear tests
• qualityPreference cache identity note/bump
• Stream honesty / stale-inventory polish

Phase 3 — Planned gaps the sweep skipped

• Footer vs help/mpv overflow parity (not dumping every chord into the footer)
• Bounded provider attempt timeline in /diagnostics
• Latest-10 export/trace retention
• ErrorShell hardening (bounded substitute for full AppErrorBoundary)

Explicitly deferred: subtitle preference learning, HLS benchmarks, full player actor, greenfield AppErrorBoundary.

Next step

Execute the plan on cursor/ad11-reliability-integration-a0e0 (subagent-driven or inline). This PR is docs-only.

  

[KitsuneKode]

Closing as an archived planning PR. Its execution sequence is superseded by the current-main provider recovery and PR-triage workboard. The remote branch is retained.