fix: add execute permission for start.sh to prevent runtime crash

The container was failing with 'permission denied' on /app/start.sh.
Adding chmod +x after COPY ensures the entrypoint is executable.

Dockerfile

@@ -29,6 +29,9 @@ RUN pip install --no-cache-dir -r requirements.txt
 # App Code (achtet .dockerignore)
 COPY . /app
 
+# Fix permissions for entrypoint
+RUN chmod +x /app/start.sh
+
 # Workspace
 RUN mkdir -p /workspace