Function normalize_id_input 

pub fn normalize_id_input(raw: &str) -> String

Normalize any of #A1, A1, a1, TODO-00A1, TODO-00A1-EA, #A1-EA to a form find_task_file understands (uppercase, with TODO- prefix and 4-digit counter).

Pass-through for anything that does not look like a short or full ID; callers get the original string back and downstream lookup fails with the normal “not found” diagnostic.