Add matrix_client_commet_scheme, like every other web client role has

The Commet role was the only playbook-installed web client without a
`_scheme` variable to go with its `_hostname` and `_path_prefix`, so
anything wishing to build Commet's public URL had to reach for
`matrix_playbook_ssl_enabled` itself.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

group_vars/matrix_servers

@@ -4718,6 +4718,8 @@ matrix_client_element_element_call_url: "{{ matrix_element_call_public_url if ma
 
 matrix_client_commet_enabled: false
 
+matrix_client_commet_scheme: "{{ 'https' if matrix_playbook_ssl_enabled else 'http' }}"
+
 matrix_client_commet_hostname: "commet.{{ matrix_domain }}"
 
 matrix_client_commet_container_http_host_bind_port: "{{ (matrix_playbook_service_host_bind_interface_prefix ~ '8766') if matrix_playbook_service_host_bind_interface_prefix else '' }}"

roles/custom/matrix-client-commet/defaults/main.yml

@@ -10,6 +10,9 @@ matrix_client_commet_enabled: true
 # The git branch, tag, or SHA to build from
 matrix_client_commet_version: "main"
 
+# The scheme used for serving Commet.
+matrix_client_commet_scheme: https
+
 # The hostname at which Commet is served (e.g. commet.example.com)
 matrix_client_commet_hostname: ""