Fixed: Allow language switch key on external keyboards (#4923)

Handle KEYCODE_LANGUAGE_SWITCH to allow keyboard layout switching
on external keyboards by passing the event to system handler.

Fixes #4133

Co-authored-by: uncher <36965412+uncher@users.noreply.github.com>

terminal-view/src/main/java/com/termux/view/TerminalView.java

@@ -782,6 +782,8 @@ public final class TerminalView extends View {
         } else if (event.getAction() == KeyEvent.ACTION_MULTIPLE && keyCode == KeyEvent.KEYCODE_UNKNOWN) {
             mTermSession.write(event.getCharacters());
             return true;
+        } else if (keyCode == KeyEvent.KEYCODE_LANGUAGE_SWITCH) {
+            return super.onKeyDown(keyCode, event);
         }
 
         final int metaState = event.getMetaState();