Dockerfile: add set -ex debug output

Dockerfile

@@ -3,27 +3,36 @@ FROM python:3.11
 ENV DEBIAN_FRONTEND=noninteractive
 ENV PIP_NO_CACHE_DIR=1
 
-# python:3.11 基于 Debian bookworm，自带完整 apt 源
-RUN apt-get update && apt-get install -y --no-install-recommends \
+# 显式源 + 调试输出
+RUN set -ex \
+ && echo "deb http://deb.debian.org/debian bookworm main" > /etc/apt/sources.list \
+ && echo "deb http://deb.debian.org/debian-security bookworm-security main" >> /etc/apt/sources.list \
+ && echo "deb http://deb.debian.org/debian bookworm-updates main" >> /etc/apt/sources.list \
+ && apt-get update \
+ && apt-get install -y --no-install-recommends \
     wget xz-utils ca-certificates \
     libxi6 libxext6 libxrender1 libxfixes3 libxxf86vm1 \
     libxkbcommon0 libsm6 libgl1 libglu1-mesa \
-    && rm -rf /var/lib/apt/lists/*
+ && rm -rf /var/lib/apt/lists/* \
+ && echo "=== APT packages installed ==="
 
 # Blender 4.2.9 LTS
 ARG BLENDER_VERSION=4.2.9
-RUN wget -q "https://download.blender.org/release/Blender4.2/blender-${BLENDER_VERSION}-linux-x64.tar.xz" -O /tmp/blender.tar.xz \
+RUN set -ex \
+ && wget -q "https://download.blender.org/release/Blender4.2/blender-${BLENDER_VERSION}-linux-x64.tar.xz" -O /tmp/blender.tar.xz \
  && tar -xf /tmp/blender.tar.xz -C /opt \
  && mv /opt/blender-${BLENDER_VERSION}-linux-x64 /opt/blender \
- && rm /tmp/blender.tar.xz
+ && rm /tmp/blender.tar.xz \
+ && /opt/blender/blender --version \
+ && echo "=== Blender installed ==="
+
 ENV PATH="/opt/blender:${PATH}"
 
-# HF 非 root 用户
 RUN useradd -m -u 1000 appuser
 WORKDIR /app
 
 COPY requirements.txt .
-RUN pip install -r requirements.txt
+RUN set -ex && pip install -r requirements.txt && echo "=== Python deps installed ==="
 
 COPY app.py worker.py ./