update import (#13)

Author: Jintao-Huang

src/mcore_bridge/model/__init__.py

@@ -3,4 +3,4 @@
 from .constant import ModelType
 from .gpt_model import GPTModel
 from .mm_gpt_model import MultimodalGPTModel
-from .register import get_mcore_model, get_mcore_model_type, get_model_meta
+from .register import MODEL_MAPPING, get_mcore_model, get_mcore_model_type, get_model_meta