Enable automatic RealESRGAN model download for texture generation

- Uncommented the automatic download of RealESRGAN_x4plus.pth in prepare_env()
- Added directory creation to ensure ckpt folder exists
- This fixes the missing texture generation functionality
- The model was supposed to be downloaded automatically but was commented out

gradio_app.py

@@ -311,8 +311,9 @@ if ENV == 'Huggingface':
 
         print("cd /home/user/app/hy3dpaint/differentiable_renderer/ && bash compile_mesh_painter.sh")
         os.system("cd /home/user/app/hy3dpaint/DifferentiableRenderer && bash compile_mesh_painter.sh")
-        # print("wget https://github.com/xinntao/Real-ESRGAN/releases/download/v0.1.0/RealESRGAN_x4plus.pth -P /home/user/app/hy3dpaint/ckpt")
-        # os.system("wget https://github.com/xinntao/Real-ESRGAN/releases/download/v0.1.0/RealESRGAN_x4plus.pth -P /home/user/app/hy3dpaint/ckpt")
+        print("Downloading RealESRGAN model for texture enhancement...")
+        os.makedirs("/home/user/app/hy3dpaint/ckpt", exist_ok=True)
+        os.system("wget https://github.com/xinntao/Real-ESRGAN/releases/download/v0.1.0/RealESRGAN_x4plus.pth -P /home/user/app/hy3dpaint/ckpt")
 
     def check():
         import custom_rasterizer