refactor(annotation): 简化文本标注编辑器的段落管理功能

- 移除段落统计相关的数据结构和缓存逻辑
- 删除段落切换确认对话框和自动保存选项
- 简化段落加载和状态管理流程
- 将段落列表视图替换为简单的进度显示
- 更新API接口以支持单段内容获取
- 重构后端服务实现单段内容查询功能

runtime/datamate-python/app/module/annotation/interface/editor.py

@@ -19,8 +19,8 @@ from app.db.session import get_db
 from app.module.annotation.schema.editor import (
     EditorProjectInfo,
     EditorTaskListResponse,
+    EditorTaskSegmentResponse,
     EditorTaskResponse,
-    EditorTaskSegmentsResponse,
     UpsertAnnotationRequest,
     UpsertAnnotationResponse,
 )
@@ -90,15 +90,16 @@ async def get_editor_task(
 
 @router.get(
     "/projects/{project_id}/tasks/{file_id}/segments",
-    response_model=StandardResponse[EditorTaskSegmentsResponse],
+    response_model=StandardResponse[EditorTaskSegmentResponse],
 )
-async def list_editor_task_segments(
+async def get_editor_task_segment(
     project_id: str = Path(..., description="标注项目ID（t_dm_labeling_projects.id）"),
     file_id: str = Path(..., description="文件ID（t_dm_dataset_files.id）"),
+    segment_index: int = Query(..., ge=0, alias="segmentIndex", description="段落索引（从0开始）"),
     db: AsyncSession = Depends(get_db),
 ):
     service = AnnotationEditorService(db)
-    result = await service.get_task_segments(project_id, file_id)
+    result = await service.get_task_segment(project_id, file_id, segment_index)
     return StandardResponse(code=200, message="success", data=result)