test(frontend): add unit tests for Projects list components

Add comprehensive test coverage for projects list components:
- ProjectCard.test.tsx: Card rendering, status badges, actions menu
- ProjectFilters.test.tsx: Search, filters, view mode toggle
- ProjectsGrid.test.tsx: Grid/list layout, loading, empty states

30 tests covering rendering, interactions, and edge cases.

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

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

frontend/tests/components/projects/ProjectsGrid.test.tsx

@@ -0,0 +1,107 @@
+/**
+ * ProjectsGrid Component Tests
+ */
+
+import { render, screen, fireEvent } from '@testing-library/react';
+import { ProjectsGrid } from '@/components/projects/ProjectsGrid';
+import type { ProjectListItem } from '@/lib/api/hooks/useProjects';
+
+// Mock next-intl navigation
+jest.mock('@/lib/i18n/routing', () => ({
+  Link: ({ children, href }: { children: React.ReactNode; href: string }) => (
+    <a href={href}>{children}</a>
+  ),
+}));
+
+describe('ProjectsGrid', () => {
+  const mockProjects: ProjectListItem[] = [
+    {
+      id: 'proj-1',
+      name: 'Project One',
+      description: 'First project',
+      status: 'active',
+      complexity: 'medium',
+      progress: 50,
+      openIssues: 5,
+      activeAgents: 2,
+      lastActivity: '5 min ago',
+      createdAt: '2025-01-01T00:00:00Z',
+      owner: { id: 'user-1', name: 'User One' },
+    },
+    {
+      id: 'proj-2',
+      name: 'Project Two',
+      description: 'Second project',
+      status: 'paused',
+      complexity: 'high',
+      progress: 75,
+      openIssues: 3,
+      activeAgents: 0,
+      lastActivity: '1 day ago',
+      createdAt: '2025-01-02T00:00:00Z',
+      owner: { id: 'user-2', name: 'User Two' },
+    },
+  ];
+
+  it('renders project cards', () => {
+    render(<ProjectsGrid projects={mockProjects} />);
+
+    expect(screen.getByText('Project One')).toBeInTheDocument();
+    expect(screen.getByText('Project Two')).toBeInTheDocument();
+  });
+
+  it('renders in grid layout by default', () => {
+    const { container } = render(<ProjectsGrid projects={mockProjects} />);
+
+    // Should have grid classes
+    expect(container.firstChild).toHaveClass('grid');
+  });
+
+  it('renders in list layout when viewMode is list', () => {
+    const { container } = render(<ProjectsGrid projects={mockProjects} viewMode="list" />);
+
+    // Should have space-y-4 class for list view
+    expect(container.firstChild).toHaveClass('space-y-4');
+  });
+
+  it('shows loading skeletons when isLoading is true', () => {
+    const { container } = render(<ProjectsGrid projects={[]} isLoading />);
+
+    // Should render skeleton cards
+    expect(container.querySelectorAll('.animate-pulse').length).toBeGreaterThan(0);
+  });
+
+  it('shows empty state when no projects and no filters', () => {
+    render(<ProjectsGrid projects={[]} hasFilters={false} />);
+
+    expect(screen.getByText('No projects found')).toBeInTheDocument();
+    expect(screen.getByText('Get started by creating your first project')).toBeInTheDocument();
+    expect(screen.getByRole('link', { name: /Create Project/i })).toBeInTheDocument();
+  });
+
+  it('shows filter-adjusted empty state when no projects with filters', () => {
+    render(<ProjectsGrid projects={[]} hasFilters={true} />);
+
+    expect(screen.getByText('No projects found')).toBeInTheDocument();
+    expect(screen.getByText('Try adjusting your filters or search query')).toBeInTheDocument();
+  });
+
+  it('calls onProjectClick when project card is clicked', () => {
+    const onProjectClick = jest.fn();
+    render(<ProjectsGrid projects={mockProjects} onProjectClick={onProjectClick} />);
+
+    // Click on the first project card
+    const projectCards = screen.getAllByRole('button');
+    fireEvent.click(projectCards[0]);
+
+    expect(onProjectClick).toHaveBeenCalledWith(mockProjects[0]);
+  });
+
+  it('applies custom className', () => {
+    const { container } = render(
+      <ProjectsGrid projects={mockProjects} className="custom-class" />
+    );
+
+    expect(container.firstChild).toHaveClass('custom-class');
+  });
+});