Implement the simplest orchestrator command: start work on an existing task.
Trigger
User sends: 'work on t-123' or 'start t-123' or similar
Behavior
1. Parse task ID from message
2. Validate task exists and is in workable state (Open/InProgress)
3. Spawn pi-orchestrate.sh as subprocess
4. Send progress updates to user
5. Report final result (done/needs-help)
Implementation
- Add pattern matching in message handler for 'work on t-XXX'
- Use System.Process to spawn pi-orchestrate.sh
- Capture stdout/stderr for progress
- Send Telegram messages at key points:
- 'Starting work on t-123: <title>'
- 'Iteration 1: Coder running...'
- 'Iteration 1: Reviewing...'
- '✅ Done! Commit: abc123' or '❌ Needs help: <reason>'
Files
- Omni/Agent/Telegram.hs (add command handler)
- Omni/Agent/Telegram/Orchestrator.hs (new, subprocess management)