refactor(state): address review recommendations for store and prefs

src/state/__tests__/store.test.ts

@@ -34,18 +34,12 @@ describe('game store nav and prefs', () => {
     const state = useGameStore.getState();
     state.setActivePanel('story');
     expect(useGameStore.getState().activePanel).toBe('story');
-
-    // Reset back
-    useGameStore.getState().setActivePanel('play');
   });
 
   it('updates selectedStoryNodeId via setSelectedStoryNodeId', () => {
     const state = useGameStore.getState();
     state.setSelectedStoryNodeId('node-1');
     expect(useGameStore.getState().selectedStoryNodeId).toBe('node-1');
-
-    state.setSelectedStoryNodeId(null);
-    expect(useGameStore.getState().selectedStoryNodeId).toBeNull();
   });
 
   it('toggles collapsed action groups in prefs', () => {