feat(supervisor): add priority-based sequential scheduling for daily agents
Implement true priority-based scheduling where agents in the same priority group
run in parallel, but different priority groups execute sequentially. This ensures
higher priority agents (lower numbers) complete before lower priority ones start.
Key changes:
- Main loop now runs at 1-second intervals for responsiveness
- Subsystems manage their own timing internally (health checks, agent scheduling)
- Non-blocking state machine for scheduled agent execution
- 5-minute timeout per priority group prevents indefinite blocking
- Fast shutdown signal handling (1-second granularity)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>