disentangle model from tuner and rename modules

Former-commit-id: 02cbf91e7e424f8379c1fed01b82a5f7a83b6947

src/llmtuner/eval/template.py

@@ -1,7 +1,7 @@
 from dataclasses import dataclass
 from typing import TYPE_CHECKING, Dict, List, Tuple
 
-from llmtuner.eval.constants import CHOICES
+from llmtuner.extras.constants import CHOICES
 
 if TYPE_CHECKING:
     from datasets import Dataset