feat: crash recovery, service_failed monitoring, broker health fields, command expiry sweep

- Add GET /api/clients/crashed endpoint (process_status=crashed or stale heartbeat)
- Add restart_app command action with same lifecycle + lockout as reboot_host
- Scheduler: crash auto-recovery loop (CRASH_RECOVERY_ENABLED flag, lockout, MQTT publish)
- Scheduler: unconditional command expiry sweep per poll cycle (sweep_expired_commands)
- Listener: subscribe to infoscreen/+/service_failed; persist service_failed_at + unit
- Listener: extract broker_connection block from health payload; persist reconnect_count + last_disconnect_at
- DB migration b1c2d3e4f5a6: service_failed_at, service_failed_unit, mqtt_reconnect_count, mqtt_last_disconnect_at on clients
- Add GET /api/clients/service_failed and POST /api/clients/<uuid>/clear_service_failed
- Monitoring overview API: include mqtt_reconnect_count + mqtt_last_disconnect_at per client
- Frontend: orange service-failed alert panel (hidden when empty, auto-refresh, quittieren action)
- Frontend: MQTT reconnect count + last disconnect in client detail panel
- MQTT auth hardening: listener/scheduler/server use env credentials; broker enforces allow_anonymous false
- Client command lifecycle foundation: ClientCommand model, reboot_host/shutdown_host, full ACK lifecycle
- Docs: TECH-CHANGELOG, DEV-CHANGELOG, MQTT_EVENT_PAYLOAD_GUIDE, copilot-instructions updated
- Add implementation-plans/, RESTART_VALIDATION_CHECKLIST.md, TODO.md

docker-compose.yml

@@ -19,6 +19,10 @@ services:
       - DB_CONN=mysql+pymysql://${DB_USER}:${DB_PASSWORD}@db/${DB_NAME}
       - DB_URL=mysql+pymysql://${DB_USER}:${DB_PASSWORD}@db/${DB_NAME}
       - API_BASE_URL=http://server:8000
+      - MQTT_BROKER_HOST=${MQTT_BROKER_HOST:-mqtt}
+      - MQTT_BROKER_PORT=${MQTT_BROKER_PORT:-1883}
+      - MQTT_USER=${MQTT_USER}
+      - MQTT_PASSWORD=${MQTT_PASSWORD}
       - ENV=${ENV:-development}
       - FLASK_SECRET_KEY=${FLASK_SECRET_KEY:-dev-secret-key-change-in-production}
       - DEFAULT_SUPERADMIN_USERNAME=${DEFAULT_SUPERADMIN_USERNAME:-superadmin}
@@ -70,6 +74,17 @@ services:
     image: eclipse-mosquitto:2.0.21 # ✅ GUT: Version ist bereits spezifisch
     container_name: infoscreen-mqtt
     restart: unless-stopped
+    command: >
+      sh -c 'set -eu;
+      : "$${MQTT_USER:?MQTT_USER not set}";
+      : "$${MQTT_PASSWORD:?MQTT_PASSWORD not set}";
+      touch /mosquitto/config/passwd;
+      chmod 600 /mosquitto/config/passwd;
+      mosquitto_passwd -b /mosquitto/config/passwd "$${MQTT_USER}" "$${MQTT_PASSWORD}";
+      if [ -n "$${MQTT_CANARY_USER:-}" ] && [ -n "$${MQTT_CANARY_PASSWORD:-}" ]; then
+        mosquitto_passwd -b /mosquitto/config/passwd "$${MQTT_CANARY_USER}" "$${MQTT_CANARY_PASSWORD}";
+      fi;
+      exec mosquitto -c /mosquitto/config/mosquitto.conf'
     volumes:
       - ./mosquitto/config:/mosquitto/config
       - ./mosquitto/data:/mosquitto/data
@@ -77,13 +92,18 @@ services:
     ports:
       - "1883:1883" # Standard MQTT
       - "9001:9001" # WebSocket (falls benötigt)
+    environment:
+      - MQTT_USER=${MQTT_USER}
+      - MQTT_PASSWORD=${MQTT_PASSWORD}
+      - MQTT_CANARY_USER=${MQTT_CANARY_USER:-}
+      - MQTT_CANARY_PASSWORD=${MQTT_CANARY_PASSWORD:-}
     networks:
       - infoscreen-net
     healthcheck:
       test:
         [
           "CMD-SHELL",
-          "mosquitto_pub -h localhost -t test -m 'health' || exit 1",
+          "mosquitto_pub -h localhost -u $$MQTT_USER -P $$MQTT_PASSWORD -t test -m 'health' || exit 1",
         ]
       interval: 30s
       timeout: 5s
@@ -169,13 +189,18 @@ services:
     environment:
       # HINZUGEFÜGT: Datenbank-Verbindungsstring
       - DB_CONN=mysql+pymysql://${DB_USER}:${DB_PASSWORD}@db/${DB_NAME}
-      - MQTT_BROKER_URL=mqtt
-      - MQTT_PORT=1883
+      - MQTT_BROKER_HOST=${MQTT_BROKER_HOST:-mqtt}
+      - MQTT_BROKER_PORT=${MQTT_BROKER_PORT:-1883}
+      - MQTT_USER=${MQTT_USER}
+      - MQTT_PASSWORD=${MQTT_PASSWORD}
       - POLL_INTERVAL_SECONDS=${POLL_INTERVAL_SECONDS:-30}
       - POWER_INTENT_PUBLISH_ENABLED=${POWER_INTENT_PUBLISH_ENABLED:-false}
       - POWER_INTENT_HEARTBEAT_ENABLED=${POWER_INTENT_HEARTBEAT_ENABLED:-true}
       - POWER_INTENT_EXPIRY_MULTIPLIER=${POWER_INTENT_EXPIRY_MULTIPLIER:-3}
       - POWER_INTENT_MIN_EXPIRY_SECONDS=${POWER_INTENT_MIN_EXPIRY_SECONDS:-90}
+      - CRASH_RECOVERY_ENABLED=${CRASH_RECOVERY_ENABLED:-false}
+      - CRASH_RECOVERY_GRACE_SECONDS=${CRASH_RECOVERY_GRACE_SECONDS:-180}
+      - CRASH_RECOVERY_LOCKOUT_MINUTES=${CRASH_RECOVERY_LOCKOUT_MINUTES:-15}
     networks:
       - infoscreen-net