Improve Dockerfile robustness for Render build

Dockerfile

@@ -7,9 +7,10 @@ ENV PYTHONUNBUFFERED 1
 ENV PORT 10000
 
 # Install system dependencies
-RUN apt-get update && apt-get install -y --no-install-recommends \
+ENV DEBIAN_FRONTEND=noninteractive
+RUN apt-get update --fix-missing && apt-get install -y --no-install-recommends \
     ffmpeg \
-    libgl1-mesa-glx \
+    libgl1 \
     libglib2.0-0 \
     build-essential \
     && apt-get clean \