focus method
Focuses the cursor, starting the blink animation if in blink mode.
Implementation
(CursorModel, Cmd?) focus() {
final newCursor = copyWith(
focus: true,
blink: _mode == CursorMode.hide, // Show cursor unless hidden
);
if (_mode == CursorMode.blink) {
return (newCursor, newCursor._blinkCmd());
}
return (newCursor, null);
}