test(app): restore timeline e2e server health mock

[Hona]

Summary

• make the shared Playwright mock server respond to the required global health endpoint
• reuse that mock in the two timeline regression specs instead of maintaining duplicate route tables
• allow the streamed timeline regression to provide its queued SSE events through the shared mock

Cause

After global server health moved into app startup state, these timeline tests still returned an empty object for /global/health. The app correctly treated the mocked server as unhealthy and stayed on the reconnect screen before reaching any timeline assertion.

Validation

• bunx playwright test e2e/smoke/session-timeline.spec.ts e2e/regression/session-timeline-collapse-state.spec.ts e2e/regression/session-timeline-context-resize.spec.ts — 4 passed
• bun typecheck in packages/app
• push hook: bun turbo typecheck — 18 successful

[Copilot]

Pull request overview

Restores e2e timeline regression specs by extending the shared Playwright mock server to satisfy the new /global/health startup probe and to support per-test SSE event injection, then refactors the two timeline regression specs to use the shared mock instead of duplicate route tables.

Changes:

• Add /global/health response and optional events factory to the shared mock server, threading queued events through sse().
• Replace inline route tables in two regression specs with mockOpenCodeServer calls.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
packages/app/e2e/utils/mock-server.ts	Adds healthy /global/health response and optional events factory for SSE payloads.
packages/app/e2e/regression/session-timeline-context-resize.spec.ts	Removes duplicated route table and uses the shared mock helper.
packages/app/e2e/regression/session-timeline-collapse-state.spec.ts	Removes duplicated route table and forwards queued events via the shared mock.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.