fix: 修复路径问题

tests/data/test_checkpoint.py

@@ -4,7 +4,7 @@ import torch.distributed as dist
 
 from torch.optim import AdamW
 from torch.optim.lr_scheduler import CosineAnnealingLR
-from khaosz.data.checkpoint import Checkpoint
+from khaosz.data.serialization import Checkpoint
 from khaosz.parallel.setup import get_rank, spawn_parallel_fn
 
 def test_single_process():

tests/trainer/test_early_stopping.py

@@ -3,7 +3,7 @@ import torch
 import numpy as np
 from khaosz.config import *
 from khaosz.trainer import *
-from khaosz.data.checkpoint import Checkpoint
+from khaosz.data.serialization import Checkpoint
 
 def test_early_stopping_simulation(base_test_env, early_stopping_dataset):
     """Simulate early stopping behavior"""