feat(graph): add Federation Graph page and enhance coverage

Adds a new Federation Graph page to display subgraphs and their 
schemas. Implements loading state and error handling. Enhances 
coverage reporting by including 'lcov' format for better insights 
into test coverage metrics.

app/components/__tests__/OrganizationSwitcher.spec.ts

@@ -0,0 +1,46 @@
+import { mount } from '@vue/test-utils'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { ref } from 'vue'
+
+const mockSelectOrganization = vi.fn()
+
+const mockOrganizations = [
+  { id: '1', name: 'Org 1', apiKeys: [{ name: 'key1' }, { name: 'key2' }] },
+  { id: '2', name: 'Org 2', apiKeys: [{ name: 'key3' }] },
+  { id: '3', name: 'Org 3', apiKeys: [] },
+]
+
+// TODO: Add more comprehensive component tests once vitest module mocking issues are resolved
+// For now, the component is indirectly tested through useOrganizationSelector tests
+// and manual testing shows it works correctly
+
+describe('OrganizationSwitcher - Single Organization', () => {
+  beforeEach(() => {
+    vi.resetModules()
+    mockSelectOrganization.mockClear()
+
+    // Mock with single organization
+    vi.mock('~/composables/useOrganizationSelector', () => ({
+      useOrganizationSelector: () => ({
+        organizations: ref([mockOrganizations[0]]),
+        selectedOrganization: ref(mockOrganizations[0]),
+        selectedOrgId: ref('1'),
+        selectOrganization: mockSelectOrganization,
+      }),
+    }))
+  })
+
+  it('should show a chip for single organization', async () => {
+    const module = await import('../OrganizationSwitcher.vue')
+    const wrapper = mount(module.default)
+
+    const html = wrapper.html()
+
+    // Should show chip
+    expect(html).toContain('v-chip')
+    expect(html).toContain('Org 1')
+
+    // Menu should not exist
+    expect(html).not.toContain('v-menu')
+  })
+})