Add quick toggles to the grab bar

Beside the gear: full keyboard, hold keys, and the numeric keypad,
navigation and function key sections, each behind a drawn icon and lit
while on. Section toggles hide when the layout lacks the section. The
grab pill narrows when a small window leaves it less room.

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

src/CMakeLists.txt

@@ -39,6 +39,8 @@ set(SLOPOSK_QML_FILES
     ResizeHandle.qml
     SectionHeader.qml
     SettingsButton.qml
+    BarToggle.qml
+    QuickToggles.qml
     SettingsPanel.qml
     ProblemList.qml
     ToggleRow.qml