update: dockerfile ffmpeg issue

Dockerfile

@@ -1,23 +1,26 @@
-FROM python:3.9
+FROM python:3.9-slim
 
 # Install system dependencies
 RUN apt-get update && apt-get install -y \
     ffmpeg \
     imagemagick \
-    && rm -rf /var/lib/apt/lists/*
+    && apt-get clean && rm -rf /var/lib/apt/lists/*
 
 # Create directories with proper permissions
 WORKDIR /app
 RUN mkdir -p /app/resources/{temp_video,audio,fonts,intro} \
-    && chmod -R 777 /app/resources
+    && chmod -R 755 /app/resources
 
 # Set up temp directory with proper permissions
 RUN mkdir -p /tmp/moviepy \
-    && chmod -R 777 /tmp/moviepy
+    && chmod -R 1777 /tmp/moviepy  # Use 1777 for sticky bit on temp directories
+
+# Set TMPDIR environment variable
+ENV TMPDIR=/tmp/moviepy
 
 # Copy and install requirements
 COPY requirements.txt .
-RUN pip install -r requirements.txt
+RUN pip install --no-cache-dir -r requirements.txt
 
 # Copy application code
 COPY . .
@@ -40,7 +43,7 @@ RUN echo '<policymap> \
 # Set proper permissions
 RUN chown -R nobody:nogroup /app \
     && chmod -R 755 /app \
-    && chmod -R 777 /tmp
+    && chmod -R 1777 /tmp
 
 # Use non-root user
 USER nobody