v0.5.0

Breaking changes

• Replace the Dispatcher API (ListenFunc, EventType, NewEvent, Event) with type-safe On[T] and Emit.
• Remove string EventType constants and the Event{type, payload} envelope; events are now plain structs.
• Remove the per-dialog Events field in favor of typed OnResponse callbacks.

Features

• Add generic type-safe event handling via On[T] and Emit.
• Add EventEmitter interface with BaseEventEmitter and SetEventEmitter for wrapping event dispatch.
• Add typed OnResponse callbacks to MessageDialog, InputDialog, ListDialog and TabListDialog.

Improvements

• Route events by Go type instead of strings.
• Dispatch event handlers synchronously and in order.
• Drop the golang.org/x/sync dependency.