Fix startup hang: 添加模型预下载步骤

Dockerfile

@@ -97,6 +97,28 @@ RUN ls -la $HOME/app/code/ImportLDraw/__init__.py || \
 RUN pip install --no-cache-dir --upgrade pip && \
     pip install --no-cache-dir -r requirements.txt
 
+# 预下载所有模型权重（避免运行时下载卡住）
+RUN echo "📥 Pre-downloading model weights during build..." && \
+    python -c "\
+import os; \
+os.makedirs('/data/.huggingface', exist_ok=True); \
+os.environ['HF_HOME'] = '/data/.huggingface'; \
+os.environ['HF_HUB_CACHE'] = '/data/.huggingface/hub'; \
+os.environ['TRANSFORMERS_CACHE'] = '/data/.huggingface/transformers'; \
+from huggingface_hub import hf_hub_download; \
+print('Downloading shape_gpt.safetensors (7.17 GB)...'); \
+hf_hub_download(repo_id='0xZohar/object-assembler-models', filename='shape_gpt.safetensors', cache_dir='/data/.huggingface'); \
+print('Downloading shape_tokenizer.safetensors (1.09 GB)...'); \
+hf_hub_download(repo_id='0xZohar/object-assembler-models', filename='shape_tokenizer.safetensors', cache_dir='/data/.huggingface'); \
+print('Downloading fine-tuned adapter (1.68 GB)...'); \
+hf_hub_download(repo_id='0xZohar/object-assembler-models', filename='save_shape_cars_whole_p_rot_scratch_4mask_randp.safetensors', cache_dir='/data/.huggingface'); \
+print('Downloading CLIP model (~600 MB)...'); \
+from transformers import CLIPModel, CLIPProcessor; \
+CLIPModel.from_pretrained('openai/clip-vit-base-patch32', cache_dir='/data/.huggingface'); \
+CLIPProcessor.from_pretrained('openai/clip-vit-base-patch32', cache_dir='/data/.huggingface'); \
+print('✅ All models pre-downloaded')" && \
+    echo "✅ Model weights cached in /data/.huggingface"
+
 # 创建启动脚本（先启动 Xvfb，再运行应用）
 RUN echo '#!/bin/bash\n\
 echo "🖥️  启动虚拟显示服务器 Xvfb..."\n\