chore: container automatisch ins netzwerk proxy-net haengen

docker-compose: service ist jetzt zusaetzlich am externen netzwerk "proxy-net"
(fest), das bei jedem `docker compose up` automatisch verbunden wird - neben
dem bisherigen env-konfigurierbaren NPM-netzwerk.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

license-backend/docker-compose.yml

@@ -19,12 +19,22 @@ services:
       # Named volume → data (SQLite DB) survives container recreation/redeploy.
       - license-data:/data
     networks:
+      # Always join the reverse-proxy network automatically on every deploy,
+      # plus the (optional) env-configurable NPM network.
+      - proxy-net
       - npm
 
 networks:
+  # Shared reverse-proxy network. The container is attached automatically by
+  # `docker compose up`. It must already exist (your proxy stack creates it);
+  # if not, create it once:  docker network create proxy-net
+  proxy-net:
+    external: true
+    name: proxy-net
   # The network Nginx Proxy Manager already runs on. Find it with:
   #   docker network ls
   # then set NPM_NETWORK in .env (e.g. NPM_NETWORK=npm_default).
+  # If you only use proxy-net, you can delete this block and the "npm" entry above.
   npm:
     external: true
     name: ${NPM_NETWORK:-npm_default}