refactor(monitoring): move grafana into the main compose stack

Owner request: one 'docker compose up -d' should bring the whole system up —
no separate monitoring project to start for the dashboards.

- docker-compose.yml: grafana service (procurement-grafana, loopback :3001,
  default+shared networks, obs datasource env) + grafana_data volume;
  provisioning and dashboard JSONs stay in ./monitoring/grafana/ (no file
  moves, provisioning unchanged)
- docker-compose.prod.yml: GRAFANA_ADMIN_PASSWORD forced via the existing
  ${VAR:?} pattern (local keeps a lenient default, prod refuses defaults)
- monitoring/docker-compose.monitoring.yml: grafana service + volume removed
  (no name/port conflict); glitchtip/prometheus/loki stay server-side as before
- docs updated: grafana restarts on app deploys are harmless (settings live
  in the volume); SSH-tunnel posture unchanged

Verified locally: both compose files validate; 'docker compose up -d' starts
all 10 services incl. procurement-grafana; BotPostgres datasource health OK;
all 3 dashboards provisioned in the fresh volume; monitoring compose no
longer contains grafana; old monitoring-grafana container removed; port
still loopback-only.

monitoring/docker-compose.monitoring.yml

@@ -85,33 +85,12 @@ services:
       - shared
     restart: unless-stopped
 
-  grafana:
-    image: grafana/grafana:11.6.3
-    container_name: monitoring-grafana
-    mem_limit: 256m
-    environment:
-      GF_SECURITY_ADMIN_USER: admin
-      GF_SECURITY_ADMIN_PASSWORD: ${GRAFANA_ADMIN_PASSWORD:?set GRAFANA_ADMIN_PASSWORD in .env}
-      GF_USERS_ALLOW_SIGN_UP: "false"
-      GF_SERVER_ROOT_URL: ${GRAFANA_ROOT_URL:-http://localhost:3001/}
-      # Bot-observability Postgres datasource (provisioned from datasources.yml)
-      OBS_DB_HOST: postgres
-      OBS_DB_PORT: "5432"
-      OBS_DB_NAME: procurement
-      OBS_DB_USER: ${OBS_READER_USER:-obs_reader}
-      OBS_DB_PASSWORD: ${PROCUREMENT_BOT_OBS_READER_PASSWORD:-}
-    volumes:
-      - grafana_data:/var/lib/grafana
-      - ./grafana/provisioning:/etc/grafana/provisioning:ro
-      - ./grafana/dashboards:/var/lib/grafana/dashboards:ro
-    ports:
-      - "127.0.0.1:3001:3000"
-    networks:
-      - monitoring
-      - shared   # reaches the app postgres for the bot_traces/bot_trace_events datasource
-    restart: unless-stopped
-
   # ------------------------------------------------------------------ logs --
+  # NOTE (2026-10-25): the grafana service MOVED to the main docker-compose.yml
+  # (owner decision: one `docker compose up -d` brings the app + grafana up
+  # together). It still reads its provisioning + dashboards from
+  # ./monitoring/grafana/ — see the main compose file for env/ports.
+
   loki:
     image: grafana/loki:3.5.0
     container_name: monitoring-loki
@@ -202,5 +181,4 @@ networks:
 volumes:
   glitchtip_postgres_data:
   prometheus_data:
-  grafana_data:
   loki_data: