Closes#1249
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
- **New Features**
- Introduced components for customizing fonts, including Google and
custom font options.
- Enhanced theme customization by simplifying theme objects and adding
new font customization options.
- Implemented dynamic font injection for web pages based on
user-selected font configurations.
- **Bug Fixes**
- Fixed a condition in theme template card rendering to correctly check
avatar enablement.
- Corrected font property handling across various components to support
both string and object types.
- **Refactor**
- Updated option properties in RadioButtons component to be readonly.
- Simplified logic for setting CSS variables for fonts, including checks
for font types and existence.
- **Documentation**
- Added constants and schemas for supporting new font types in theme
customization.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
