#169 · SimpleX /api/event-announce + /api/job-announce receivers + safety-net poller

Context

Workers push announcements to the bot via webhooks, backed by a poller that catches missed deliveries (a fire-and-forget webhook alone silently dropped Signal event broadcasts for 36 days once). SimpleX's express app exposes only /health.

Acceptance criteria

• [ ] POST /api/event-announce and POST /api/job-announce (auth X-Bot-API-Key -> getBotApiKey()) broadcast to the right SimpleX groups.
• [ ] A safety-net poller (<=60s) picks up announcements stuck pending.
• [ ] Poller registered in index.ts, stopped on shutdown.

Technical hints

• Signal reference: /api/event-announce + scheduler/event-announcement-scheduler.ts.
• SimpleX target: add routes to the express app in src/src/index.ts (the app created ~L50); new scheduler/event-announcement-scheduler.ts.
• Never read an env API key inline — always getBotApiKey()/botAuthHeaders().

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