Add (native) Traefik support to matrix-client-hydrogen

Previously, it had to go through matrix-nginx-proxy.
It's exposed to Traefik directly via container labels now

Serving at a path other than `/` doesn't work well yet.

roles/custom/matrix-client-hydrogen/tasks/setup_install.yml

@@ -52,7 +52,7 @@
     group: "{{ matrix_user_groupname }}"
   with_items:
     - {src: "{{ role_path }}/templates/nginx.conf.j2", name: "nginx.conf"}
-  when: "item.src is not none"
+    - {src: "{{ role_path }}/templates/labels.j2", name: "labels"}
 
 - name: Ensure Hydrogen Docker image is built
   community.docker.docker_image:
@@ -65,6 +65,11 @@
       pull: true
   when: "matrix_client_hydrogen_container_image_self_build | bool"
 
+- name: Ensure Hydrogen container network is created
+  community.general.docker_network:
+    name: "{{ matrix_client_hydrogen_container_network }}"
+    driver: bridge
+
 - name: Ensure matrix-client-hydrogen.service installed
   ansible.builtin.template:
     src: "{{ role_path }}/templates/systemd/matrix-client-hydrogen.service.j2"