fix(web): P4-1 restore graceful degradation for missions/tasks fetch on project detail

apps/web/src/spa/pages/project-detail.spec.tsx

@@ -134,17 +134,36 @@ describe('ProjectDetailPage', () => {
     expect(container.querySelector('[role="dialog"]')).toBeNull();
   });
 
-  it('renders a visible alert when any project detail request fails and lets the user navigate back', async () => {
+  it('renders the project with an empty missions tab when the missions request fails', async () => {
     apiMock
       .mockResolvedValueOnce(projectFixtures[0])
       .mockRejectedValueOnce(new Error('Missions request failed'))
       .mockResolvedValueOnce(taskFixtures.filter((task) => task.projectId === 'project-1'));
 
+    await renderProjectDetailPage();
+
+    expect(container.textContent).toContain('Mosaic Stack');
+    expect(container.querySelector('[role="alert"]')).toBeNull();
+
+    await act(async () => {
+      clickButtonByText('Missions (0)');
+    });
+
+    expect(container.textContent).toContain('No missions for this project');
+  });
+
+  it('renders a visible alert when the project request fails and lets the user navigate back', async () => {
+    apiMock
+      .mockRejectedValueOnce(new Error('Project request failed'))
+      .mockResolvedValueOnce(missionFixtures)
+      .mockResolvedValueOnce(taskFixtures.filter((task) => task.projectId === 'project-1'));
+
     const router = await renderProjectDetailPage();
 
     const alert = container.querySelector('[role="alert"]');
     expect(alert).toBeTruthy();
-    expect(alert?.textContent).toContain('Missions request failed');
+    expect(alert?.textContent).toContain('Project request failed');
+    expect(container.textContent).not.toContain('Mosaic Stack');
 
     await act(async () => {
       clickButtonByText('Back to projects');

apps/web/src/spa/pages/project-detail.tsx

@@ -76,8 +76,8 @@ export function ProjectDetailPage(): ReactElement {
 
     void Promise.all([
       api<Project>('/api/projects/' + id),
-      api<Mission[]>('/api/missions'),
+      api<Mission[]>('/api/missions').catch(() => [] as Mission[]),
-      api<Task[]>('/api/tasks?projectId=' + id),
+      api<Task[]>('/api/tasks?projectId=' + id).catch(() => [] as Task[]),
     ])
       .then(([loadedProject, allMissions, loadedTasks]) => {
         if (cancelled) return;