feat: add batch-delete API endpoint, replace N+1 frontend calls

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/backend/routers/files.py

@@ -169,6 +169,34 @@ async def delete_file(
     return {"message": f"已删除 {filename}"}
 
 
+@router.post("/batch-delete")
+async def batch_delete_files(
+    req: BatchDeleteRequest,
+    current_user: dict = Depends(get_current_user),
+):
+    """Batch delete files from disk and clean up relation records."""
+    dir_map = {"input": _input_dir, "output": _output_dir, "result": _result_dir}
+    deleted = 0
+    errors = []
+    for item in req.files:
+        d = item.get("directory", "")
+        fname = item.get("filename", "")
+        if d not in dir_map or not fname:
+            errors.append(f"无效参数: {d}/{fname}")
+            continue
+        file_path = dir_map[d] / fname
+        try:
+            if file_path.exists():
+                size = file_path.stat().st_size
+                file_path.unlink()
+                deleted += 1
+                _record_file_action(fname, d, size, "delete", current_user.get("username"))
+            _cleanup_relation_for_deleted_file(d, fname)
+        except Exception as e:
+            errors.append(f"{fname}: {str(e)}")
+    return {"deleted": deleted, "errors": errors}
+
+
 @router.post("/clear/{directory}")
 async def clear_directory(
     directory: str,
@@ -224,6 +252,10 @@ class RelationDeleteRequest(BaseModel):
     ids: List[int]
 
 
+class BatchDeleteRequest(BaseModel):
+    files: list[dict]
+
+
 def _cleanup_relation_for_deleted_file(directory: str, filename: str):
     """Clean up relation table when a file is deleted."""
     import sqlite3