fix(renderer): reset kitty keyboard protocol on alt screen switch

We need to reset the kitty keyboard protocol when switching between main
and alt screens. This is because kitty maintains separate keyboard
protocol registries for each screen, and failing to reset the protocol
can lead to issues such as the inability to use the Ctrl key in some
editor that don't support kitty's keyboard protocol.

Author: aymanbagabas

cursed_renderer.go

@@ -144,6 +144,14 @@ func (s *cursedRenderer) close() (err error) {
 	// so that we can restore them when we start the renderer again. This is
 	// used when the user suspends the program and then resumes it.
 	if lv := s.lastView; lv != nil { //nolint:nestif
+		// NOTE: The Kitty keyboard specs specify that the terminal should have
+		// two registries for the main and alt screens. We disable keyboard
+		// enhancements whenever we enter/exit alt screen mode in
+		// [cursedRenderer.flush].
+		// Here, we reset the keyboard protocol of the last screen used
+		// assuming the other screen is already reset when we switched screens.
+		_, _ = s.buf.WriteString(ansi.KittyKeyboard(0, 1))
+
 		if lv.AltScreen {
 			enableAltScreen(s, false, true)
 		} else {
@@ -194,9 +202,6 @@ func (s *cursedRenderer) close() (err error) {
 		if lv.ProgressBar != nil && lv.ProgressBar.State != ProgressBarNone {
 			_, _ = s.scr.WriteString(ansi.ResetProgressBar)
 		}
-
-		// NOTE: This needs to happen after we exit the alt screen.
-		_, _ = s.scr.WriteString(ansi.KittyKeyboard(0, 1))
 	}
 
 	if err := s.scr.Flush(); err != nil {
@@ -493,6 +498,10 @@ func (s *cursedRenderer) flush(closing bool) error {
 
 	var buf bytes.Buffer
 	if shouldUpdateAltScreen {
+		// We always disable keyboard enhancements when switching screens
+		// because the terminal is expected to have two different keyboard
+		// registries for main and alt screens.
+		_, _ = buf.WriteString(ansi.KittyKeyboard(0, 1))
 		if view.AltScreen {
 			// Entering alt screen mode.
 			buf.WriteString(ansi.SetModeAltScreenSaveCursor)