Fix Streamlit port handling for HF Docker Space

Dockerfile

@@ -9,4 +9,16 @@ COPY . .
 
 EXPOSE 7860
 
-CMD ["streamlit", "run", "app.py", "--server.address=0.0.0.0"]
+FROM python:3.10-slim
+
+WORKDIR /app
+
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY . .
+
+EXPOSE 7860
+
+CMD streamlit run app.py --server.address=0.0.0.0 --server.port=${PORT:-7860}
+