Function stop_watching 

pub fn stop_watching(
    registry: &WatcherRegistry,
    dir: &Path,
) -> Result<Value, McpError>

Stop watching a directory. Returns a JSON summary including final stats.

Errors

• Returns ErrorCode::InternalError if the watcher registry mutex is poisoned.
• Returns ErrorCode::FileNotFound if no active watcher is registered for the canonicalized dir.