Closes: [BS-3506](https://linear.app/affine-design/issue/BS-3506/edgeless-text-默认改为黑色)
### Dark
<img width="691" alt="Screenshot 2025-05-19 at 19 32 52" src="https://github.com/user-attachments/assets/2927d13b-0300-4293-8f8f-7891fd87a680" />
### Light
<img width="639" alt="Screenshot 2025-05-19 at 19 33 05" src="https://github.com/user-attachments/assets/4429f6f9-b374-4b17-87f4-ae09204f1538" />
<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **New Features**
- Improved edgeless text block styling to support theme-based color, font, and alignment settings.
- **Style**
- Updated the default text color in edgeless text blocks to black, with support for separate dark and light mode colors.
- **Bug Fixes**
- Ensured the color picker and block rendering reflect the updated default color.
- **Tests**
- Adjusted tests and snapshots to expect the new default color and theme-based color structure.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Closes: [BS-2909](https://linear.app/affine-design/issue/BS-2909/新增highlighter)
### What's Changed!
Currently the highlighter tool is very similar to brush, but for the future, it's a standalone module.
* Added `Highlighter` element model
* Added `Highlighter` tool
* Added `Highlighter` entry to the global toolbar
fundon
