fix: commit template upload atomically

backend/app/services/template_service.py

@@ -46,16 +46,30 @@ def store_template_file(file: UploadFile) -> tuple[str, bytes]:
     return stored_path, content
 
 
-def create_template_record(db: Session, name: str, file_path: str, type: str = "report") -> Template:
+def create_template_record(
+    db: Session,
+    name: str,
+    file_path: str,
+    type: str = "report",
+    commit: bool = True,
+) -> Template:
     """创建模板记录"""
     tmpl = Template(name=name, type=type, original_file_path=file_path)
     db.add(tmpl)
-    db.commit()
+    if commit:
+        db.commit()
+    else:
+        db.flush()
     db.refresh(tmpl)
     return tmpl
 
 
-def save_template_blocks(db: Session, template_id: int, blocks: list[dict]) -> list[TemplateBlock]:
+def save_template_blocks(
+    db: Session,
+    template_id: int,
+    blocks: list[dict],
+    commit: bool = True,
+) -> list[TemplateBlock]:
     """批量保存解析出的模板区域。"""
     records = [
         TemplateBlock(
@@ -74,5 +88,8 @@ def save_template_blocks(db: Session, template_id: int, blocks: list[dict]) -> l
     ]
 
     db.add_all(records)
-    db.commit()
+    if commit:
+        db.commit()
+    else:
+        db.flush()
     return records