모델 업로드 구조 완성

include/utils/snowflake.h

@@ -20,12 +20,12 @@ struct Snowflake {
   std::vector<char> Serialize() {
     std::vector<char> serialized;
     serialized.insert(serialized.end(), &snowflake,
-                      &snowflake + sizeof(std::uint64_t));
+                      &snowflake + sizeof(snowflake));
     return serialized;
   }
 };
 
-Snowflake GenerateID();
+Snowflake GenerateID(std::uint16_t instance);
 
 }  // namespace Chattr