fix(status-bar): invalidate settled branch CI

[beruro]

Summary

Follow-up to #653 after it merged before the review fixes could be attached.

• invalidate branch PR/CI status after push and pull-request creation
• force a refresh when local HEAD changes, including hidden-to-visible transitions
• retain a five-minute safety refresh for remote-only changes while keeping fast polling bounded
• add producer-boundary and hook lifecycle regression coverage

Validation

• pnpm exec tsc --noEmit
• ESLint on changed files
• 20 focused tests across push/PR producers, polling policy, and hook lifecycle