Persist canonical task lifecycle state

[JulioMCruz]

What changed

• Map task status transitions to a canonical dispatch state.
• Clear claim, retry reservation, prior delivery error, and worker-protocol state when work reaches Review or Done.
• Add policy tests for every lifecycle mapping.

Why

The production mixed-runtime E2E exposed stale retry/claim metadata after completion. That let the dispatcher retry finished work and made the UI unable to distinguish queued, working, review, and completed tasks reliably.

Validation

• npm test: 45/45 passed
• npm run build: passed
• npm run lint: blocked by the repository's pre-existing ESLint 9 configuration mismatch (no eslint.config.*); no lint configuration is changed here

Rollout

Deploy this service before repeating Desktop JOURNEY-PROJECT-001.