fix(docker): correct port mapping and improve container startup

- Fix port mapping from 5001:5001 to 5001:5000 to match internal application port
- Add entrypoint script for proper database initialization and seeding
- Set PORT environment variable to 5000 for consistency
- Update Dockerfile to use entrypoint script with proper line ending handling

calorie_tracker_app/Dockerfile

@@ -17,8 +17,12 @@ COPY . .
 # Create data directory
 RUN mkdir -p /app/data
 
-# Expose port
-EXPOSE 5001
+# Fix line endings for entrypoint script (in case of Windows checkout) and make executable
+RUN sed -i 's/\r$//' entrypoint.sh && \
+    chmod +x entrypoint.sh
 
-# Run commands to init db, seed data, and start server
-CMD ["sh", "-c", "flask init-db && flask seed-db && gunicorn -w 4 -b 0.0.0.0:5001 app:app"]
+# Expose port (default 5000)
+EXPOSE 5000
+
+# Use entrypoint script to init db, seed data, and start server
+ENTRYPOINT ["./entrypoint.sh"]