<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **Refactor**
- Improved the internal structure and clarity of ID handling during import processes, leading to more maintainable and modular code. No changes to user-facing functionality.
- **Chores**
- Enhanced type definitions for import events to improve code readability and maintainability. No impact on end-user experience.
<!-- 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**
- Introduced new exports related to workspace management, making additional workspace features available.
- **Refactor**
- Updated how document and workspace types are imported and exported, consolidating and reorganizing module structure.
- Shifted dependency management for document instances to use an internal provider mechanism.
- Streamlined and centralized type imports across various modules.
- **Bug Fixes**
- Removed an unused schema definition to improve code clarity.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
### Changed
- Added support for changing the preview offset during dragging.
- Fixed the preview rendering for embed block and surface-ref block
- Resolved an issue where the host element might be reused in certain cases, which could cause unexpected behavior
- Moved viewport-related constants and methods to a more appropriate location