Add Athena configuration and secrets to inventory and templates

- Updated vault.yml.example to include Athena secrets: secret key, DB password, OAuth client ID, and client secret.
- Modified puck.incus.yml to add Athena service and configuration details, including user, group, directory, port, and domain.
- Updated titania.incus.yml to change OAuth client ID and secret variable names for consistency with Athena.
- Added Athena configuration to mcpo config template, including URL and authorization headers.

ansible/gitea/deploy.yml

@@ -187,8 +187,8 @@
           --config {{ gitea_config_file }}
           --name "{{ gitea_oauth_name }}"
           --provider openidConnect
-          --key "{{ gitea_oauth_client_id }}"
-          --secret "{{ gitea_oauth_client_secret }}"
+          --key "{{ gitea_oauth2_client_id }}"
+          --secret "{{ gitea_oauth2_client_secret }}"
           --auto-discover-url "https://id.ouranos.helu.ca/.well-known/openid-configuration"
           --scopes "{{ gitea_oauth_scopes }}"
           --skip-local-2fa