- add process health bridge and monitoring flow between display_manager and simclient
- publish health + warn/error log topics over MQTT
- standardize log/payload/screenshot timestamps to UTC (Z) to avoid DST drift
- improve video handling: python-vlc fullscreen enforcement and runtime PID reporting
- update README and copilot instructions with monitoring architecture and troubleshooting
- add Phase 3 monitoring implementation documentation
- update gitignore for new runtime/log artifacts
Switch to Paho v2 callbacks; add loop_start() and reconnect_delay_set() for auto-reconnect
Rework on_connect/on_disconnect to v2 signatures; handle session_present and reconnection flows
Gate heartbeats with client.is_connected() and add short retry on rc=4 (NO_CONN)
Re-send discovery after reconnect; ensure re-subscription to all topics
Add startup terminal message with ISO timestamp in simclient.py
Docs: update README and Copilot instructions with reconnection/heartbeat guidance and benign rc=4 notes
