The merge delivers four major bodies of work. The dominant theme is FN-3588, which adds an "immediate wake" override to the message inbox API, exposes it in the MailboxModal UI, and updates `agent-heartbeat.ts` and `executor.ts` to honor the override alongside timer/signal triggers. FN-3705 gates re
Fusion-Task-Id: FN-3588
This merge lands five FN-3593 commits establishing a test isolation contract with a new `scripts/check-test-isolation.mjs` guard that scans for accidental `beforeEach`/`afterEach`/`beforeAll`/`afterAll` in setup helpers, plus per-package `setup-test-isolation.ts` bootstraps that canonicalize the pat
Fusion-Task-Id: FN-3593
- Replace text input with always-open dropdown in MessageComposer component
- Update MessageComposer tests to cover dropdown behavior
- Remove .message-composer-input from shared CSS rule
