test(frontend): comprehensive test coverage improvements and bug fixes

- Raise coverage thresholds to 90% statements/lines/functions, 85% branches
- Add comprehensive tests for ProjectDashboard, ProjectWizard, and all wizard steps
- Add tests for issue management: IssueDetailPanel, BulkActions, IssueFilters
- Expand IssueTable tests with keyboard navigation, dropdown menu, edge cases
- Add useIssues hook tests covering all mutations and optimistic updates
- Expand eventStore tests with selector hooks and additional scenarios
- Expand useProjectEvents tests with error recovery, ping events, edge cases
- Add PriorityBadge, StatusBadge, SyncStatusIndicator fallback branch tests
- Add constants.test.ts for comprehensive constant validation

Bug fixes:
- Fix false positive rollback test to properly verify onMutate context setup
- Replace deprecated substr() with substring() in mock helpers
- Fix type errors: ProjectComplexity, ClientMode enum values
- Fix unused imports and variables across test files
- Fix @ts-expect-error directives and method override signatures

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/tests/lib/stores/eventStore.test.ts

@@ -10,7 +10,7 @@ import { EventType, type ProjectEvent } from '@/lib/types/events';
  */
 function createMockEvent(overrides: Partial<ProjectEvent> = {}): ProjectEvent {
   return {
-    id: `event-${Math.random().toString(36).substr(2, 9)}`,
+    id: `event-${Math.random().toString(36).substring(2, 11)}`,
     type: EventType.AGENT_MESSAGE,
     timestamp: new Date().toISOString(),
     project_id: 'project-123',
@@ -253,3 +253,118 @@ describe('Event Store', () => {
     });
   });
 });
+
+/**
+ * Tests for Selector Hooks
+ */
+import { renderHook } from '@testing-library/react';
+import { useProjectEventsFromStore, useLatestEvent, useEventCount } from '@/lib/stores/eventStore';
+
+describe('Event Store Selector Hooks', () => {
+  beforeEach(() => {
+    // Reset store state
+    useEventStore.setState({
+      eventsByProject: {},
+      maxEvents: 100,
+    });
+  });
+
+  describe('useProjectEventsFromStore', () => {
+    it('should return empty array for non-existent project', () => {
+      const { result } = renderHook(() => useProjectEventsFromStore('non-existent'));
+      expect(result.current).toEqual([]);
+    });
+
+    it('should return events for existing project', () => {
+      const event = createMockEvent();
+      useEventStore.getState().addEvent(event);
+
+      const { result } = renderHook(() => useProjectEventsFromStore('project-123'));
+      expect(result.current).toHaveLength(1);
+      expect(result.current[0]).toEqual(event);
+    });
+
+    it('should update when events are added', () => {
+      const { result, rerender } = renderHook(() => useProjectEventsFromStore('project-123'));
+      expect(result.current).toHaveLength(0);
+
+      useEventStore.getState().addEvent(createMockEvent());
+      rerender();
+
+      expect(result.current).toHaveLength(1);
+    });
+  });
+
+  describe('useLatestEvent', () => {
+    it('should return undefined for non-existent project', () => {
+      const { result } = renderHook(() => useLatestEvent('non-existent'));
+      expect(result.current).toBeUndefined();
+    });
+
+    it('should return undefined for empty project', () => {
+      const { result } = renderHook(() => useLatestEvent('project-123'));
+      expect(result.current).toBeUndefined();
+    });
+
+    it('should return the last event added', () => {
+      const event1 = createMockEvent({ id: 'event-1' });
+      const event2 = createMockEvent({ id: 'event-2' });
+      const event3 = createMockEvent({ id: 'event-3' });
+
+      useEventStore.getState().addEvents([event1, event2, event3]);
+
+      const { result } = renderHook(() => useLatestEvent('project-123'));
+      expect(result.current?.id).toBe('event-3');
+    });
+
+    it('should update when a new event is added', () => {
+      const event1 = createMockEvent({ id: 'event-1' });
+      useEventStore.getState().addEvent(event1);
+
+      const { result, rerender } = renderHook(() => useLatestEvent('project-123'));
+      expect(result.current?.id).toBe('event-1');
+
+      const event2 = createMockEvent({ id: 'event-2' });
+      useEventStore.getState().addEvent(event2);
+      rerender();
+
+      expect(result.current?.id).toBe('event-2');
+    });
+  });
+
+  describe('useEventCount', () => {
+    it('should return 0 for non-existent project', () => {
+      const { result } = renderHook(() => useEventCount('non-existent'));
+      expect(result.current).toBe(0);
+    });
+
+    it('should return correct count for existing project', () => {
+      const events = [
+        createMockEvent({ id: 'event-1' }),
+        createMockEvent({ id: 'event-2' }),
+        createMockEvent({ id: 'event-3' }),
+      ];
+      useEventStore.getState().addEvents(events);
+
+      const { result } = renderHook(() => useEventCount('project-123'));
+      expect(result.current).toBe(3);
+    });
+
+    it('should update when events are added or removed', () => {
+      const { result, rerender } = renderHook(() => useEventCount('project-123'));
+      expect(result.current).toBe(0);
+
+      useEventStore.getState().addEvent(createMockEvent({ id: 'event-1' }));
+      rerender();
+      expect(result.current).toBe(1);
+
+      useEventStore.getState().addEvent(createMockEvent({ id: 'event-2' }));
+      rerender();
+      expect(result.current).toBe(2);
+
+      useEventStore.getState().clearProjectEvents('project-123');
+      rerender();
+      expect(result.current).toBe(0);
+    });
+  });
+});