fix(sequencer): expose 9000 metrics port from docker

lez/sequencer/service/Dockerfile

@@ -63,8 +63,9 @@ COPY --from=builder --chown=sequencer_service_user:sequencer_service_user /usr/l
 
 VOLUME /var/lib/sequencer_service
 
-# Expose default port
+# Expose default ports
 EXPOSE 3040
+EXPOSE 9000
 
 # Health check (TODO #244: Replace when a real health endpoint is available)
 HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \

lez/sequencer/service/docker-compose.yml

@@ -18,6 +18,7 @@ services:
     container_name: sequencer_service
     ports:
       - "3040:3040"
+      - "9000:9000"
     volumes:
       # Mount configuration file
       - ./configs/docker/sequencer_config.json:/etc/sequencer_service/sequencer_config.json

monitoring/prometheus/prometheus.yml

@@ -6,10 +6,5 @@ scrape_configs:
   - job_name: sequencer
     metrics_path: /metrics
     static_configs:
-      # `sequencer_service:9000` resolves when monitoring runs inside the
-      # all-in-one compose network. `host.docker.internal:9000` resolves when
-      # the sequencer runs natively on the host and only monitoring runs in Docker.
-      # Whichever is unreachable stays `down`.
       - targets:
-          - sequencer_service:9000
           - host.docker.internal:9000