refactor: migrate to ModelRegistry.create factory

ModelRegistry's public constructor became private in pi-coding-agent 0.64.
Direct `new ModelRegistry(...)` calls no longer compile. Switch the five
production sites to the factory (`ModelRegistry.create`) and update the
four test modules that mocked the class as a constructor to now mock it
as an object with `create` and `inMemory` static methods.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/cli/src/commands/__tests__/daemon.test.ts

@@ -553,7 +553,10 @@ vi.mock("@mariozechner/pi-coding-agent", () => ({
   DefaultPackageManager: vi.fn().mockImplementation(() => ({
     resolve: vi.fn().mockResolvedValue({ extensions: [] }),
   })),
-  ModelRegistry: vi.fn().mockImplementation(() => mocks.modelRegistry),
+  ModelRegistry: {
+    create: vi.fn(() => mocks.modelRegistry),
+    inMemory: vi.fn(() => mocks.modelRegistry),
+  },
   SettingsManager: {
     create: vi.fn(() => ({})),
   },

packages/cli/src/commands/__tests__/dashboard.test.ts

@@ -345,7 +345,10 @@ vi.mock("@mariozechner/pi-coding-agent", () => ({
   DefaultPackageManager: vi.fn().mockImplementation(() => ({
     resolve: vi.fn().mockResolvedValue({ extensions: [] }),
   })),
-  ModelRegistry: vi.fn().mockImplementation(() => mockModelRegistry),
+  ModelRegistry: {
+    create: vi.fn(() => mockModelRegistry),
+    inMemory: vi.fn(() => mockModelRegistry),
+  },
   SettingsManager: {
     create: vi.fn(() => ({})),
   },
@@ -459,8 +462,9 @@ describe("runDashboard — AuthStorage & ModelRegistry wiring", () => {
 
     await runDashboard(0, {});
 
-    expect(ModelRegistry).toHaveBeenCalledTimes(1);
-    const registryAuthStorage = (ModelRegistry as ReturnType<typeof vi.fn>).mock.calls[0][0];
+    const createMock = ModelRegistry.create as unknown as ReturnType<typeof vi.fn>;
+    expect(createMock).toHaveBeenCalledTimes(1);
+    const registryAuthStorage = createMock.mock.calls[0][0];
     expect(registryAuthStorage).not.toBe(mockAuthStorage);
     expect(registryAuthStorage.getApiKey).toBeTypeOf("function");
   });

packages/cli/src/commands/__tests__/serve.test.ts

@@ -592,7 +592,10 @@ vi.mock("@mariozechner/pi-coding-agent", () => ({
   DefaultPackageManager: vi.fn().mockImplementation(() => ({
     resolve: vi.fn().mockResolvedValue({ extensions: [] }),
   })),
-  ModelRegistry: vi.fn().mockImplementation(() => mocks.modelRegistry),
+  ModelRegistry: {
+    create: vi.fn(() => mocks.modelRegistry),
+    inMemory: vi.fn(() => mocks.modelRegistry),
+  },
   SettingsManager: {
     create: vi.fn(() => ({})),
   },