The main window controller was created as a local variable in
ConnectWindowController.authSucceeded and never retained — ARC
deallocated it immediately, which destroyed the VoiceCatClient
(connection silently dropped), nil'd every button's weak target
(clicks did nothing), and killed event delivery (channel list,
messages, voice never worked). Symptom: TOFU (in the retained
connect controller) worked, but everything in the main window
was a zombie shell.
Fix: store the MainWindowController in a new field on
ConnectWindowController (which AppDelegate retains for the app's
lifetime). Also add NSLog diagnostics in deinit/bootstrap/handleEvent
so lifecycle and event delivery are observable from the terminal
or Console.app.