Three RED tests pin Pattern 4 (handshake) and Pattern 5 / Pitfall 4
(port reconnect on disconnect) contracts:
handshake.test.ts:
- 'sends OFFSCREEN_READY after listener registration' — exactly one
OFFSCREEN_READY emitted at module load, AFTER onMessage.addListener
port.test.ts:
- 'connects on module load' — chrome.runtime.connect called once
- 'reconnects when port disconnects' — firing onDisconnect triggers
immediate re-connect (Pitfall 4 idle-timer reset)
chrome.runtime is stubbed locally (no vitest-chrome dependency added).
No 'as any' / no '@ts-ignore'; casts are 'as unknown as T'.
Plan 04 must wire OFFSCREEN_READY send + port.connect({ name:
'video-keepalive' }) + onDisconnect-driven reconnect at the import-side
effect layer of src/offscreen/recorder.ts.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
