Initial work on matrix-homeserver-proxy role and eliminating matrix-nginx-proxy

This is still very far from usable.

Various bridges and bots are still talking to
`matrix-nginx-proxy` instead of the new `matrix-homeserver-proxy` role.
These services need to be reworked. While reworking them,
various cleanups are being done as well as adding Traefik-labels to
those that need them.

roles/custom/matrix-bridge-mautrix-facebook/tasks/main.yml

@@ -1,14 +1,5 @@
 ---
 
-- tags:
-    - setup-all
-    - setup-nginx-proxy
-    - install-all
-    - install-nginx-proxy
-  block:
-    - when: matrix_mautrix_facebook_enabled | bool and matrix_mautrix_facebook_appservice_public_enabled | bool
-      ansible.builtin.include_tasks: "{{ role_path }}/tasks/inject_into_nginx_proxy.yml"
-
 - tags:
     - setup-all
     - setup-mautrix-facebook