feat: complete huihui square avatar workflows

digital-avatar-app/backend/responses.py

@@ -0,0 +1,6 @@
+def ok(data=None, message="success"):
+    return {"code": 200, "message": message, "data": data}
+
+
+def fail(message="error", code=400):
+    return {"code": code, "message": message, "data": None}