refactor: convert template.yml files to template.toml format

- Updated the script to convert 'template.yml' files to 'template.toml' files during directory processing.
- Added new 'template.toml' files for Backrest and BlinkO blueprints with appropriate configuration settings.

blueprints/backrest/template.toml

@@ -0,0 +1,11 @@
+[variables]
+main_domain = "${domain}"
+
+[config]
+env = ["TZ=Europe/Paris"]
+mounts = []
+
+[[config.domains]]
+serviceName = "backrest"
+port = 9_898
+host = "${main_domain}"