Add a role to install 'ntfy' push-notification server.

This commit adds a 'matrix-ntfy' role that runs Ntfy server in Docker with
simple configuration, and plumbing to add the role to the playbook.

TODO: documentation, self-check, database persistence.

roles/matrix-nginx-proxy/tasks/setup_nginx_proxy.yml

@@ -138,6 +138,13 @@
     mode: 0644
   when: matrix_nginx_proxy_proxy_sygnal_enabled|bool
 
+- name: Ensure Matrix nginx-proxy configuration for ntfy domain exists
+  template:
+    src: "{{ role_path }}/templates/nginx/conf.d/matrix-ntfy.conf.j2"
+    dest: "{{ matrix_nginx_proxy_confd_path }}/matrix-ntfy.conf"
+    mode: 0644
+  when: matrix_nginx_proxy_proxy_ntfy_enabled|bool
+
 - name: Ensure Matrix nginx-proxy configuration for Matrix domain exists
   template:
     src: "{{ role_path }}/templates/nginx/conf.d/matrix-domain.conf.j2"
@@ -288,6 +295,12 @@
     state: absent
   when: "not matrix_nginx_proxy_proxy_sygnal_enabled|bool"
 
+- name: Ensure Matrix nginx-proxy configuration for ntfy domain deleted
+  file:
+    path: "{{ matrix_nginx_proxy_confd_path }}/matrix-ntfy.conf"
+    state: absent
+  when: "not matrix_nginx_proxy_proxy_ntfy_enabled|bool"
+
 - name: Ensure Matrix nginx-proxy homepage for base domain deleted
   file:
     path: "{{ matrix_nginx_proxy_data_path }}/matrix-domain/index.html"