feat(state): nav panel store and expanded prefs

src/state/__tests__/prefs.test.ts

@@ -15,7 +15,12 @@ describe('prefs', () => {
   });
 
   it('returns defaults when localStorage empty', () => {
-    expect(getPrefs()).toEqual({ storyOpenMode: 'auto', actionDetailMode: 'inline' });
+    expect(getPrefs()).toEqual({
+      storyOpenMode: 'auto',
+      actionDetailMode: 'inline',
+      collapsedActionGroups: {},
+      showEventLog: true,
+    });
   });
 
   it('round-trips updated prefs', () => {
@@ -23,3 +28,11 @@ describe('prefs', () => {
     expect(getPrefs().storyOpenMode).toBe('manual');
   });
 });
+
+describe('expanded prefs', () => {
+  it('defaults collapsedActionGroups and showEventLog', () => {
+    const prefs = getPrefs();
+    expect(prefs.collapsedActionGroups).toEqual({});
+    expect(prefs.showEventLog).toBe(true);
+  });
+});