- Add OpHealth RPC operation to protocol
- Implement handleHealth() with DB ping and 1s timeout
- Returns status (healthy/degraded/unhealthy), uptime, cache metrics
- Update TryConnect() to use health check instead of ping
- Add 'bd daemon --health' CLI command with JSON output
- Track cache hits/misses for metrics
- Unhealthy daemon triggers automatic fallback to direct mode
- Health check completes in <2 seconds
Amp-Thread-ID: https://ampcode.com/threads/T-1a4889f3-77cf-433a-a704-e1c383929f48
Co-authored-by: Amp <amp@ampcode.com>