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>

qml/SettingsPanel.qml

@@ -32,6 +32,14 @@ Rectangle {
                 onToggled: checked => panel.settings.autoCapitalize = checked
             }
 
+            ToggleRow {
+                width: parent.width
+                text: qsTr("Always Show")
+                detail: qsTr("Type into any window, not just text fields")
+                checked: panel.settings.alwaysVisible
+                onToggled: checked => panel.settings.alwaysVisible = checked
+            }
+
             ToggleRow {
                 width: parent.width
                 text: qsTr("“.” Shortcut")