refactor: centralize transform constants in model.py

Co-authored-by: aider (gemini/gemini-2.5-pro-preview-05-06) <aider@aider.chat>

model.py

@@ -1,6 +1,13 @@
 import torch.nn as nn
 from PIL import Image, ImageDraw
 
+# --- Model and Transform Constants ---
+# For the custom crop transform. User can adjust these.
+TRIANGLE_CROP_WIDTH = 556
+TRIANGLE_CROP_HEIGHT = 1184
+RESIZE_DIM = 64 # Resize cropped image to this dimension (square)
+
+
 # Custom transform to crop a triangle from the lower right corner
 class CropLowerRightTriangle(object):
     """