Close [AI-193](https://linear.app/affine-design/issue/AI-193)
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## Summary by CodeRabbit
- **New Features**
- Added support for streaming structured AI chat responses as objects,
enabling richer and more interactive chat experiences.
- Chat messages now include a new field displaying structured stream
objects, such as reasoning steps, text deltas, tool calls, and tool
results.
- GraphQL APIs and queries updated to expose these structured streaming
objects in chat histories.
- Introduced a new streaming chat endpoint for object-based responses.
- **Bug Fixes**
- Improved error handling for streaming responses to ensure more robust
and informative error reporting.
- **Refactor**
- Centralized and streamlined session preparation and streaming logic
for AI chat providers.
- Unified streaming setup across multiple AI model providers.
- **Tests**
- Extended test coverage for streaming object responses to ensure
reliability and correctness.
- **Documentation**
- Updated type definitions and schemas to reflect new streaming object
capabilities in both backend and frontend code.
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Co-authored-by: DarkSky <25152247+darkskygit@users.noreply.github.com>
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## Summary by CodeRabbit
- **Chores**
- Updated Gemini model identifiers from preview versions to their latest
stable versions across prompts and provider configurations. This ensures
continued compatibility and access to the latest Gemini 2.5 Flash and
Pro models. No changes to user-facing features or prompt content.
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Support [AI-82](https://linear.app/affine-design/issue/AI-82).
Added a `TextStreamParser` class to standardize formatting of different types of AI stream chunks across providers.
### What changed?
- Created a new `TextStreamParser` class in `utils.ts` that handles formatting of various chunk types (text-delta, reasoning, tool-call, tool-result, error)
- Refactored the Anthropic, Gemini, and OpenAI providers to use this shared parser instead of duplicating formatting logic
- Added comprehensive tests for the new `TextStreamParser` class, including tests for individual chunk types and sequences of chunks
- Defined a common `AITools` type to standardize tool interfaces across providers
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## Summary by CodeRabbit
- **New Features**
- Enhanced formatting and structure for streamed AI responses, including improved handling of callouts, web search, and web crawl results.
- **Refactor**
- Streamlined and unified the processing of streamed AI response chunks across providers for more consistent output.
- **Bug Fixes**
- Improved error handling and display for streamed responses.
- **Tests**
- Added comprehensive tests to ensure correct formatting and handling of various streamed message types.
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Close [AI-125](https://linear.app/affine-design/issue/AI-125)
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## Summary by CodeRabbit
- **New Features**
- Added new provider configurations `geminiVertex` and `anthropicVertex` for Google Vertex AI in backend schema, provider classes, and admin config.
- Introduced `GeminiVertexProvider` and `AnthropicVertexProvider` classes supporting Vertex AI models with specific capabilities.
- Expanded model options for transcription prompts with newer Gemini models.
- Re-exported provider modules to include Vertex AI variants.
- **Improvements**
- Extended provider architecture to support separate Vertex AI configurations and models.
- Updated test setup to replace deprecated provider references with new Vertex variants.
- Consolidated environment variables for server testing with a single `SERVER_CONFIG`.
- **Bug Fixes**
- Updated mock models and import references in tests to align with new provider classes.
- **Chores**
- Added `@ai-sdk/google-vertex` dependency for Vertex AI support.
- Updated dependency list to include `@ai-sdk/google-vertex`.
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Wu Yue