Type into any window: fake input when no text field is focused

- KWinFakeInput (org_kde_kwin_fake_input v6, offered by KWin to the
  input-method process): keysyms with real modifier keys held
- The KWin backend uses the input method in text fields and fake input
  everywhere else, so shortcuts, terminals and the desktop get keys
- Text rules (auto-capitalization, double-space) only apply in fields
- Always Show setting keeps the keyboard up without a text field

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/input/KeyboardController.cpp

@@ -141,12 +141,11 @@ void KeyboardController::moveCursor(QPoint steps)
     repeat(qMax(0, -steps.y()), XKB_KEY_Up);
 }
 
-void KeyboardController::resetContext()
+void KeyboardController::resetContext(const TextContext &context)
 {
     m_deadKeys.cancel();
-    m_context = {};
     m_textBefore.clear();
-    autoCapitalize();
+    setContext(context);
 }
 
 void KeyboardController::setContext(const TextContext &context)