docs: promote no-debug-API principle; make monitoring ports configurable

Bench and flight share one query channel, so debugging exercises the
production path daily. Grafana/Prometheus/exporter host ports become
env-overridable for shared hosts.

simulator/docker-compose.yml

@@ -29,7 +29,7 @@ services:
       - ./data:/data:ro
       - ./monitoring:/app/monitoring:ro
     ports:
-      - "9105:9105"
+      - "${EXPORTER_PORT:-9105}:9105"
 
   prometheus:
     image: prom/prometheus:v2.53.0
@@ -37,7 +37,7 @@ services:
     volumes:
       - ./monitoring/prometheus.yml:/etc/prometheus/prometheus.yml:ro
     ports:
-      - "9090:9090"
+      - "${PROMETHEUS_PORT:-9090}:9090"
 
   grafana:
     image: grafana/grafana:11.1.0
@@ -50,6 +50,6 @@ services:
       - ./monitoring/grafana/provisioning:/etc/grafana/provisioning:ro
       - ./monitoring/grafana/dashboards:/var/lib/grafana/dashboards:ro
     ports:
-      - "3000:3000"
+      - "${GRAFANA_PORT:-3000}:3000"
     depends_on:
       - prometheus