Fix running the docker TLS stack

The latest upgrades to our frontend stack prohibited access through the
openproject.local hostname and also caused trouble with the previous setup
where the frontend stack would proxy requests to the backend.

Thus the default setup was now changed so that both frontend and backend
are exposed to the browser via different hostnames. The main service to start
will be the backend, which will redirect requests to certain assets to the frontend
service (this was already integrated into the rails routes previously).

docker-compose.yml

@@ -66,6 +66,7 @@ services:
     depends_on:
       - db
       - cache
+      - frontend
 
   worker:
     <<: *backend
@@ -77,16 +78,12 @@ services:
   frontend:
     build:
       <<: *frontend-build
-    command: "node --max_old_space_size=8096 ./node_modules/@angular/cli/bin/ng serve --host 0.0.0.0"
+    command: "node --max_old_space_size=8096 ./node_modules/@angular/cli/bin/ng serve --host 0.0.0.0 --allowed-hosts openproject-assets.local"
     volumes:
       - ".:/home/dev/openproject"
       - "${CKEDITOR_BUILD_DIR:-./frontend/src/vendor/ckeditor/}:/home/dev/openproject/frontend/src/vendor/ckeditor/"
-    environment:
-      PROXY_HOSTNAME: backend
     networks:
       - network
-    depends_on:
-      - backend
 
   db:
     image: postgres:17