feat: eager vLLM warmup and smart page titles in paginate stage

- Add warmup() to LlmProvider interface for eager subprocess startup
- ManagedVllmProvider.warmup() starts vLLM in background on project load
- ProviderRegistry.warmupAll() triggers all managed providers
- NamedProvider proxies warmup() to inner provider
- paginate stage generates LLM-powered descriptive page titles when
  available, cached by content hash, falls back to generic "Page N"
- project-mcp-endpoint calls warmupAll() on router creation so vLLM
  is loading while the session initializes

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/mcpd/tests/project-routes.test.ts

@@ -16,9 +16,12 @@ function makeProject(overrides: Partial<ProjectWithRelations> = {}): ProjectWith
     description: '',
     ownerId: 'user-1',
     proxyMode: 'direct',
+    prompt: '',
+    proxyModel: '',
     gated: true,
     llmProvider: null,
     llmModel: null,
+    serverOverrides: null,
     version: 1,
     createdAt: new Date(),
     updatedAt: new Date(),
@@ -149,6 +152,21 @@ describe('Project Routes', () => {
       expect(res.statusCode).toBe(201);
     });
 
+    it('creates a project with proxyModel', async () => {
+      const repo = mockProjectRepo();
+      vi.mocked(repo.findById).mockResolvedValue(makeProject({ name: 'pm-proj', proxyModel: 'subindex' }));
+      await createApp(repo);
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/projects',
+        payload: { name: 'pm-proj', proxyModel: 'subindex' },
+      });
+      expect(res.statusCode).toBe(201);
+      expect(repo.create).toHaveBeenCalledWith(
+        expect.objectContaining({ proxyModel: 'subindex' }),
+      );
+    });
+
     it('returns 400 for invalid input', async () => {
       const repo = mockProjectRepo();
       await createApp(repo);
@@ -186,6 +204,19 @@ describe('Project Routes', () => {
       expect(res.statusCode).toBe(200);
     });
 
+    it('updates proxyModel on a project', async () => {
+      const repo = mockProjectRepo();
+      vi.mocked(repo.findById).mockResolvedValue(makeProject({ id: 'p1' }));
+      await createApp(repo);
+      const res = await app.inject({
+        method: 'PUT',
+        url: '/api/v1/projects/p1',
+        payload: { proxyModel: 'subindex' },
+      });
+      expect(res.statusCode).toBe(200);
+      expect(repo.update).toHaveBeenCalledWith('p1', expect.objectContaining({ proxyModel: 'subindex' }));
+    });
+
     it('returns 404 when not found', async () => {
       const repo = mockProjectRepo();
       await createApp(repo);
@@ -281,4 +312,50 @@ describe('Project Routes', () => {
       expect(res.statusCode).toBe(404);
     });
   });
+
+  describe('serverOverrides', () => {
+    it('accepts serverOverrides in project create', async () => {
+      const repo = mockProjectRepo();
+      vi.mocked(repo.findById).mockResolvedValue(
+        makeProject({ name: 'override-proj', serverOverrides: { ha: { proxyModel: 'ha-special' } } }),
+      );
+      await createApp(repo);
+      const res = await app.inject({
+        method: 'POST',
+        url: '/api/v1/projects',
+        payload: { name: 'override-proj', serverOverrides: { ha: { proxyModel: 'ha-special' } } },
+      });
+      expect(res.statusCode).toBe(201);
+      expect(repo.create).toHaveBeenCalledWith(
+        expect.objectContaining({ serverOverrides: { ha: { proxyModel: 'ha-special' } } }),
+      );
+    });
+
+    it('accepts serverOverrides in project update', async () => {
+      const repo = mockProjectRepo();
+      vi.mocked(repo.findById).mockResolvedValue(makeProject({ id: 'p1' }));
+      await createApp(repo);
+      const res = await app.inject({
+        method: 'PUT',
+        url: '/api/v1/projects/p1',
+        payload: { serverOverrides: { ha: { proxyModel: 'ha-special' } } },
+      });
+      expect(res.statusCode).toBe(200);
+      expect(repo.update).toHaveBeenCalledWith('p1', expect.objectContaining({
+        serverOverrides: { ha: { proxyModel: 'ha-special' } },
+      }));
+    });
+
+    it('returns serverOverrides in project GET', async () => {
+      const repo = mockProjectRepo();
+      vi.mocked(repo.findById).mockResolvedValue(
+        makeProject({ id: 'p1', name: 'ha-proj', serverOverrides: { ha: { proxyModel: 'ha-special' } } }),
+      );
+      await createApp(repo);
+      const res = await app.inject({ method: 'GET', url: '/api/v1/projects/p1' });
+      expect(res.statusCode).toBe(200);
+      const body = res.json<{ serverOverrides: unknown }>();
+      expect(body.serverOverrides).toEqual({ ha: { proxyModel: 'ha-special' } });
+    });
+  });
 });