Move reranker to Serenity, add monitoring and mesh-mqtt-observer stacks

- ai: remove reranker service (moved to Serenity at 10.5.1.5:9787)
- ai: add LiteLLM reranker proxy entry for Serenity
- ai: configure OpenWebUI to use LiteLLM for reranking
- monitoring: add Grafana + Prometheus stack
- mesh-mqtt-observer: add new service
- automation, documents, meshtastic: misc updates

monitoring/docker-compose.yaml

@@ -0,0 +1,59 @@
+name: monitoring
+
+services:
+  prometheus:
+    image: prom/prometheus:v3.4.0
+    container_name: prometheus
+    restart: unless-stopped
+    ports:
+      - "9090:9090"
+    command:
+      - '--config.file=/etc/prometheus/prometheus.yml'
+      - '--storage.tsdb.path=/prometheus'
+      - '--storage.tsdb.retention.time=90d'
+      - '--web.enable-lifecycle'
+    volumes:
+      - /mnt/tank/docker/appdata/prometheus:/prometheus
+      - /mnt/docker-ssd/docker/compose/monitoring/prometheus.yml:/etc/prometheus/prometheus.yml:ro
+    networks:
+      - default
+
+  grafana:
+    image: grafana/grafana:13.0.1
+    container_name: grafana
+    restart: unless-stopped
+    ports:
+      - "3000:3000"
+    environment:
+      TZ: ${TZ}
+      GF_SECURITY_ADMIN_USER: ${GF_ADMIN_USER}
+      GF_SECURITY_ADMIN_PASSWORD: ${GF_ADMIN_PASS}
+      GF_SERVER_ROOT_URL: https://${GF_HOST}/
+    volumes:
+      - /mnt/tank/docker/appdata/grafana:/var/lib/grafana
+      - /mnt/docker-ssd/docker/compose/monitoring/provisioning:/etc/grafana/provisioning:ro
+    networks:
+      - pangolin
+      - default
+
+  node-exporter:
+    image: prom/node-exporter:v1.9.0
+    container_name: node-exporter
+    restart: unless-stopped
+    ports:
+      - "9100:9100"
+    command:
+      - '--path.procfs=/host/proc'
+      - '--path.sysfs=/host/sys'
+      - '--path.rootfs=/rootfs'
+      - '--collector.filesystem.mount-points-exclude=^/(sys|proc|dev|host|etc)($$|/)'
+    volumes:
+      - /proc:/host/proc:ro
+      - /sys:/host/sys:ro
+      - /:/rootfs:ro
+    networks:
+      - default
+
+networks:
+  pangolin:
+    external: true

monitoring/prometheus.yml

@@ -0,0 +1,28 @@
+global:
+  scrape_interval: 15s
+  evaluation_interval: 15s
+
+scrape_configs:
+  # ------- PlausibleDeniability (local via node-exporter) -------
+  - job_name: 'pd-node'
+    static_configs:
+      - targets: ['node-exporter:9100']
+        labels:
+          host: 'plausible-deniability'
+
+  # ------- Serenity (via Netdata Prometheus exporter) -------
+  - job_name: 'serenity-netdata'
+    metrics_path: /api/v1/allmetrics
+    params:
+      format: [prometheus]
+    static_configs:
+      - targets: ['10.5.1.5:19999']
+        labels:
+          host: 'serenity'
+
+  # ------- N.O.M.A.D. (via node-exporter) -------
+  - job_name: 'nomad-node'
+    static_configs:
+      - targets: ['10.5.1.16:9100']
+        labels:
+          host: 'nomad'

monitoring/provisioning/dashboards/dashboards.yml

@@ -0,0 +1,12 @@
+apiVersion: 1
+
+providers:
+  - name: 'default'
+    orgId: 1
+    folder: ''
+    type: file
+    disableDeletion: false
+    editable: true
+    options:
+      path: /var/lib/grafana/dashboards
+      foldersFromFilesStructure: false

monitoring/provisioning/datasources/prometheus.yml

@@ -0,0 +1,9 @@
+apiVersion: 1
+
+datasources:
+  - name: Prometheus
+    type: prometheus
+    access: proxy
+    url: http://prometheus:9090
+    isDefault: true
+    editable: true