How do I sign in or out?
`frely mcp start` signs in when needed, so a separate login is normally unnecessary. Use `frely login` to sign in on its own (add --no-browser on a machine without a browser, or --email <address> then --code <6-digit code>), and `frely logout` to sign out; logout also revokes the `frely api` authorization. To stop controlling the computer remotely, use `frely mcp stop` (pause) or `frely mcp remove` (revoke every client and uninstall the service).