fix: classification results empty and res.data access issues

Backend:
- Add GET /classifications/results endpoint with project/level/keyword filters
- Add column relationship to ClassificationResult model
- Fix test data generator to fetch column IDs from DB after bulk insert

Frontend:
- Fix request.ts interceptor to return full response body (keep total/pagination)
- Fix all pages to use res.data instead of res
- Add getClassificationResults API in classification.ts
- Implement fetchData in Classification.vue with proper filtering and pagination
- Fix same res.data issue in Category.vue, Metadata.vue, Project.vue, DataSource.vue, Dashboard.vue, Task.vue

backend/app/api/v1/classification.py

@@ -151,6 +151,54 @@ def list_templates(
     return ResponseModel(data=[TemplateOut.model_validate(i) for i in items])
 
 
+@router.get("/results", response_model=ListResponse)
+def list_results(
+    project_id: Optional[int] = Query(None),
+    level_id: Optional[int] = Query(None),
+    keyword: Optional[str] = Query(None),
+    page: int = Query(1, ge=1),
+    page_size: int = Query(20, ge=1, le=500),
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    from app.services.project_service import list_results as _list_results
+    items, total = _list_results(db, project_id=project_id, keyword=keyword, page=page, page_size=page_size)
+
+    data = []
+    for r in items:
+        col = r.column
+        table = col.table if col else None
+        database = table.database if table else None
+        source = database.source if database else None
+
+        # Filter by level_id if specified
+        if level_id and r.level_id != level_id:
+            continue
+
+        data.append({
+            "id": r.id,
+            "project_id": r.project_id,
+            "column_id": col.id if col else None,
+            "column_name": col.name if col else None,
+            "data_type": col.data_type if col else None,
+            "comment": col.comment if col else None,
+            "table_name": table.name if table else None,
+            "database_name": database.name if database else None,
+            "source_name": source.name if source else None,
+            "category_id": r.category_id,
+            "category_name": r.category.name if r.category else None,
+            "level_id": r.level_id,
+            "level_name": r.level.name if r.level else None,
+            "level_color": r.level.color if r.level else None,
+            "source": r.source,
+            "confidence": r.confidence,
+            "status": r.status,
+            "created_at": r.created_at.isoformat() if r.created_at else None,
+        })
+
+    return ListResponse(data=data, total=total, page=page, page_size=page_size)
+
+
 @router.post("/auto-classify/{project_id}")
 def auto_classify(
     project_id: int,

backend/app/models/project.py

@@ -92,6 +92,7 @@ class ClassificationResult(Base):
     updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
 
     project = relationship("ClassificationProject", back_populates="results")
+    column = relationship("DataColumn")
     category = relationship("Category")
     level = relationship("DataLevel")