feat: add Messenger worker Docker service

Reuses the app image with messenger:consume command.
Restarts automatically, with 1h time limit and 256M memory limit.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yaml

@@ -18,6 +18,14 @@ services:
       database:
         condition: service_healthy
 
+  messenger:
+    image: git.lclr.dev/thibaud-lclr/ltbxd-actorle/app:latest
+    command: ["php", "bin/console", "messenger:consume", "async", "--time-limit=3600", "--memory-limit=256M"]
+    restart: unless-stopped
+    depends_on:
+      database:
+        condition: service_healthy
+
   database:
     build:
       context: docker/database