Stack source types:

• Repository — Create the stack from Git if it does not exist on the endpoint; otherwise pull and redeploy the existing Git-backed stack.
• Manual YAML — Create the stack from inline Compose/Swarm YAML if it does not exist on the endpoint; otherwise update and redeploy the existing file-based stack. Content is validated (YAML mapping with a non-empty services section) before Portainer is called. Git-backed stacks cannot be converted this way.