Update Dockerfile

Dockerfile

@@ -1,7 +1,30 @@
 FROM python:3.10-slim
+
+# 1. System deps & working dir
 WORKDIR /app
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends \
+       build-essential \
+    && rm -rf /var/lib/apt/lists/*
+
+# 2. Pre-create data dirs with correct ownership
+#    - /app/data used at build to satisfy app.py
+#    - /mnt/data for persistent storage across space rebuilds
+RUN mkdir -p /app/data/forms /app/data/submissions \
+    && mkdir -p /mnt/data/forms /mnt/data/submissions \
+    && chown -R root:root /app/data \
+    && chown -R root:root /mnt/data
+
+# 3. Copy and install Python dependencies
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt
+
+# 4. Copy the rest of your app
 COPY . .
+
+# 5. Environment variable tells app to write under /mnt/data
+ENV DATA_DIR=/mnt/data
+
+# 6. Expose the port and launch
 EXPOSE 7860
-CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "7860"]
+CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "7860"]