- Added new required `Type` field with nvarchar(50) to `Annotation` entity.
- Updated `CHANGED_WHO` column type from nchar(100) to nvarchar(50).
- Corresponding database migration required.
- Added Annotation entity mapped to table TBSIG_DOCUMENT_RECEIVER_ELEMENT_ANNOTATION
- Included data annotations for key, required fields, and relationships
- Added conditional compilation for .NET and .NET Framework compatibility