Function agent_doc_document_changed 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn agent_doc_document_changed(
    file_path: *const c_char,
)

Record a document change event for debounce tracking.

Plugins call this on every document modification (typing, paste, undo). Used by agent_doc_await_idle to determine if the user is still editing.

Safety

file_path must be a valid, NUL-terminated UTF-8 string.