<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **New Features**
- Introduced a new pointer graphics module with tools and quick tool integration for edgeless surfaces.
- Added a quick tool button for pointer interactions in edgeless mode.
- Exposed new extension points for pointer graphics and effects.
- **Improvements**
- Integrated pointer graphics as a dependency into related packages.
- Enhanced toolbar context to support additional surface alignment modes.
- Added conditional clipboard configuration registrations for edgeless contexts across multiple block types.
- **Removals**
- Removed legacy tool and effect definitions and related quick tool exports from edgeless components.
- Streamlined extension arrays and removed unused exports for a cleaner codebase.
- Deleted obsolete utility functions and component registrations.
- **Chores**
- Updated workspace and TypeScript project references to include the new pointer graphics module.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Closes: [BS-3302](https://linear.app/affine-design/issue/BS-3302/處理-affine-中的-redos-風險)
<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **Bug Fixes**
- Improved handling of footnote definitions with varied spacing, special characters, and malformed or incomplete entries, ensuring more reliable processing and display.
- **New Features**
- Introduced advanced parsing for footnote URLs to improve accuracy and validation of footnote content.
- **Tests**
- Expanded test coverage for footnote processing to include additional edge cases and mixed content scenarios, enhancing overall robustness.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **New Features**
- Images and icons in bookmark cards are now loaded through an image proxy for improved reliability and consistency.
- Embed blocks for GitHub, Loom, and YouTube now display banner and creator images via an image proxy service for enhanced image loading.
- **Refactor**
- Simplified backend URL handling and proxy logic for images, resulting in more efficient processing and reduced complexity.
- Consolidated image proxy middleware and services into a shared adapter module for streamlined imports and improved maintainability.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Closes: [BS-3272](https://linear.app/affine-design/issue/BS-3272/footnote-适配-exa-api-返回结果)
## What's Changed
Add link preview data support (favicon, title, description) for URL references in footnotes:
- Store and display URL preview data in footnotes
- Add encoding/decoding support for favicon URLs
- Optimize link preview by using existing preview data when available
