Update Dockerfile to fix permissions and run as non-root user

Dockerfile

@@ -7,6 +7,9 @@ RUN apt-get update && apt-get install -y \
     build-essential \
     && rm -rf /var/lib/apt/lists/*
 
+# Create a non-root user
+RUN useradd -m -u 1000 chainlit_user
+
 # Copy requirements first to leverage Docker cache
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt
@@ -14,12 +17,17 @@ RUN pip install --no-cache-dir -r requirements.txt
 # Copy the rest of the application
 COPY . .
 
-# Create necessary directories
-RUN mkdir -p data/uploads
+# Create necessary directories and set permissions
+RUN mkdir -p data/uploads .files && \
+    chown -R chainlit_user:chainlit_user /app
 
 # Set environment variables
 ENV PYTHONPATH=/app
 ENV CHAINLIT_SERVER_PORT=8000
+ENV HOME=/app
+
+# Switch to non-root user
+USER chainlit_user
 
 # Expose the port
 EXPOSE 8000