feat(core): add ai model switch ui (#12266)

Close [AI-86](https://linear.app/affine-design/issue/AI-86)

![截屏2025-05-14 11.32.41.png](https://graphite-user-uploaded-assets-prod.s3.amazonaws.com/sJGviKxfE3Ap685cl5bj/b92d5c32-fa5a-4afd-93e6-3699347575be.png)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->

## Summary by CodeRabbit

- **New Features**
  - Introduced AI model switching in chat, allowing users to select from multiple AI models during conversations.
  - Added a floating menu for easy AI model selection within the chat interface.
  - Enabled visibility of the AI model switcher through a new experimental feature flag, configurable in workspace settings (canary builds only).

- **Enhancements**
  - Improved session management in the chat panel for smoother model switching and state handling.
  - Updated localization to support the new AI model switch feature in settings.

- **Bug Fixes**
  - None.

- **Chores**
  - Registered new components and services to support AI model switching functionality.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/core/src/modules/index.ts

@@ -3,6 +3,7 @@ import { type Framework } from '@toeverything/infra';
 
 import {
   configureAIButtonModule,
+  configureAIModelSwitchModule,
   configureAINetworkSearchModule,
   configureAIReasoningModule,
 } from './ai-button';
@@ -105,6 +106,7 @@ export function configureCommonModules(framework: Framework) {
   configureCommonGlobalStorageImpls(framework);
   configureAINetworkSearchModule(framework);
   configureAIReasoningModule(framework);
+  configureAIModelSwitchModule(framework);
   configureAIButtonModule(framework);
   configureTemplateDocModule(framework);
   configureBlobManagementModule(framework);