feat(server): refactor copilot (#14892)

#### PR Dependency Tree


* **PR #14892** 👈

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tests/affine-cloud-copilot/e2e/utils/test-utils.ts

@@ -61,13 +61,20 @@ export class TestUtils {
     await waitForEditorLoad(page);
   }
 
-  public async setupTestEnvironment(
-    page: Page,
-    defaultModel = 'gemini-2.5-flash'
-  ) {
-    await switchDefaultChatModel(defaultModel);
+  public async setupTestEnvironment(page: Page, defaultModel?: string) {
+    const hasExplicitModel = defaultModel !== undefined;
+    const selectedModel = defaultModel ?? 'gemini-2.5-flash';
+    await switchDefaultChatModel(selectedModel);
 
     await skipOnboarding(page.context());
+    if (hasExplicitModel) {
+      await page.context().addInitScript(model => {
+        window.localStorage.setItem(
+          'global-state:AIModelId',
+          JSON.stringify(model)
+        );
+      }, selectedModel);
+    }
     await openHomePage(page);
     await this.createNewPage(page);
   }