refactor: reorganize project structure by moving core modules and update import paths in API server

.temp/test_model_struct.py

@@ -0,0 +1,13 @@
+import torch
+from pathlib import Path
+model = torch.load('cloud_removal_model/cloud_removal_unet_best.pth', map_location='cpu')
+print(type(model))
+print("hasattr inc:", hasattr(model, 'inc'))
+if hasattr(model, 'inc'):
+    print("hasattr double_conv:", hasattr(model.inc, 'double_conv'))
+    if hasattr(model.inc, 'double_conv'):
+        print("in_channels:", model.inc.double_conv[0].in_channels)
+else:
+    for name, param in model.named_parameters():
+        print(name, param.shape)
+        break