Move roles/matrix* to roles/custom/matrix*

This paves the way for installing other roles into `roles/galaxy` using `ansible-galaxy`,
similar to how it's done in:

- https://github.com/spantaleev/gitea-docker-ansible-deploy
- https://github.com/spantaleev/nextcloud-docker-ansible-deploy

In the near future, we'll be removing a lot of the shared role code from here
and using upstream roles for it. Some of the core `matrix-*` roles have
already been extracted out into other reusable roles:

- https://github.com/devture/com.devture.ansible.role.postgres
- https://github.com/devture/com.devture.ansible.role.systemd_docker_base
- https://github.com/devture/com.devture.ansible.role.timesync
- https://github.com/devture/com.devture.ansible.role.vars_preserver
- https://github.com/devture/com.devture.ansible.role.playbook_runtime_messages
- https://github.com/devture/com.devture.ansible.role.playbook_help

We just need to migrate to those.

roles/custom/matrix-user-creator/tasks/setup.yml

@@ -0,0 +1,33 @@
+---
+
+- name: Validate Matrix users to create
+  ansible.builtin.include_tasks: "{{ role_path }}/tasks/util/validate_user.yml"
+  with_items: "{{ matrix_user_creator_users }}"
+  loop_control:
+    loop_var: user
+  # Suppress logging to avoid dumping the credentials to the shell
+  no_log: true
+
+- name: Ensure systemd is reloaded before starting the homeserver
+  ansible.builtin.service:
+    daemon_reload: true
+
+- name: Ensure homeserver is started before creating Matrix users
+  ansible.builtin.service:
+    name: "matrix-{{ matrix_homeserver_implementation }}.service"
+    state: started
+    daemon_reload: true
+  register: matrix_user_registrator_homeserver_start_result
+
+- name: Wait a while, so that the homeserver can manage to start before creating Matrix users
+  ansible.builtin.pause:
+    seconds: 7
+  when: matrix_user_registrator_homeserver_start_result.changed | bool
+
+- name: Ensure Matrix users are created
+  ansible.builtin.include_tasks: "{{ role_path }}/tasks/util/ensure_user_registered_{{ matrix_homeserver_implementation }}.yml"
+  with_items: "{{ matrix_user_creator_users }}"
+  loop_control:
+    loop_var: user
+  # Suppress logging to avoid dumping the credentials to the shell
+  no_log: true