Function detect_interpreter 

pub fn detect_interpreter(path: &Path) -> Vec<String>

Detect the interpreter for a script based on file extension.

Returns the argv prefix to spawn the appropriate interpreter for a script at path:

• .py → ["python3"]
• .sh → ["sh"]
• any other extension (or none) → ["sh"] (default to shell)

Public so downstream consumers (e.g. i-phi’s hook dispatcher) can adopt the same script-extension dispatch table phi-core uses internally for ScriptCallback, rather than re-deriving it.