<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
* Section editing now uses the full document context to ensure edits are
consistent with the overall tone, style, and structure.
* Cleaner output for edited sections, with internal markdown comments
removed.
* **Improvements**
* Enhanced instructions and descriptions for section editing, providing
clearer guidance and examples for users.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Close [AI-396](https://linear.app/affine-design/issue/AI-396)
<img width="798" height="294" alt="截屏2025-07-25 11 30 32"
src="https://github.com/user-attachments/assets/6366dab2-688b-470b-8b24-29a2d50a38c9"
/>
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## Summary by CodeRabbit
* **New Features**
* Introduced a "Section Edit" AI tool for expert editing of specific
markdown sections based on user instructions, preserving formatting and
style.
* Added a new interface and UI component for section editing, allowing
users to view, copy, insert, or save edited content directly from chat
interactions.
* **Improvements**
* Enhanced AI chat and tool rendering to support and display section
editing results.
* Updated chat input handling for improved draft management and message
sending order.
* **Other Changes**
* Registered the new section editing tool in the system for seamless
integration.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
