<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
- **New Features**
- Added enhanced error handling and user-friendly error messages in
quick search and document search menus.
- Introduced loading state indicators for search operations.
- Quick Search now provides explicit error feedback in the UI.
- **Improvements**
- Search and aggregation operations can now prefer remote or local
indexers based on user or system preference.
- Streamlined indexer logic for more consistent and reliable search
experiences.
- Refined error handling in messaging and synchronization layers for
improved stability.
- Enhanced error object handling in messaging for clearer error
propagation.
- Updated cloud workspace storage to always use IndexedDB locally and
CloudIndexer remotely.
- Shifted indexer operations to use synchronized indexer layer for
better consistency.
- Simplified indexer client by consolidating storage and sync layers.
- Improved error propagation in messaging handlers by wrapping error
objects.
- Updated document search to prioritize remote indexer results by
default.
- **Bug Fixes**
- Improved robustness of search features by handling errors gracefully
and preventing potential runtime issues.
- **Style**
- Added new styles for displaying error messages in search interfaces.
- **Chores**
- Removed the obsolete "Enable Cloud Indexer" feature flag; cloud
indexer behavior is now always enabled where applicable.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Move the `waitForSynced` method from `frontend` to `nbstore worker` to make the wait more reliable
<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit
- **New Features**
- Added explicit tracking of document updating state to indicate when data is being applied or saved.
- Introduced new methods to wait for update and synchronization completion with abort support.
- **Improvements**
- Applied throttling with leading and trailing emissions to state observables for smoother UI updates.
- Refined synchronization waiting logic for clearer separation between update completion and sync completion.
- Removed throttling in workspace selector component for more immediate state feedback.
- Updated import and clipper services to use the new synchronization waiting methods.
- Simplified asynchronous waiting logic in indexer synchronization methods.
- **Bug Fixes**
- Enhanced accuracy and reliability of document update and sync status indicators.
- **Tests**
- Increased wait timeout in avatar selection test to improve stability.
<!-- 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**
- Added clear indication and handling of read-only mode for the indexer, including updated status reporting when the indexer is read-only.
- **Bug Fixes**
- Improved state updates to accurately reflect zero activity and completion when in read-only mode.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
To close [BS-2870](https://linear.app/affine-design/issue/BS-2870/支持识别-和-[-包裹内容为公式)
## Add Markdown Preprocessor Extension and Enhanced LaTeX Support
### Markdown Preprocessor Extension
This PR introduces a new preprocessor extension for Markdown adapters that allows preprocessing of content before conversion:
Adds a new PreprocessorManager for handling text transformations
Introduces extensible preprocessor interface that supports different processing levels (block/slice/doc)
Integrates preprocessor extension into the existing Markdown adapter workflow
### LaTeX Support Enhancement
Extends LaTeX support to handle both traditional and alternative syntax:
Adds support for backslash LaTeX syntax:
Block math: ```\[...\] ``` alongside existing ```$$...$$```
Inline math: ```\(...\) ``` alongside existing ```$...$```
Implements LaTeX preprocessor to standardize syntax before conversion
Updates tests to cover both syntax variants
EYHN