Add Fly release image and local start command

Dockerfile

@@ -0,0 +1,43 @@
+FROM node:20-bookworm AS frontend
+
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends ca-certificates curl tar \
+    && rm -rf /var/lib/apt/lists/* \
+    && curl -fsSL 'https://api.adoptium.net/v3/binary/latest/21/ga/linux/x64/jdk/hotspot/normal/eclipse' -o /tmp/jdk.tar.gz \
+    && mkdir -p /opt/java \
+    && tar -xzf /tmp/jdk.tar.gz -C /opt/java --strip-components=1 \
+    && rm /tmp/jdk.tar.gz
+
+ENV JAVA_HOME=/opt/java
+ENV PATH="/opt/java/bin:${PATH}"
+WORKDIR /app/frontend
+COPY frontend/package.json frontend/package-lock.json ./
+RUN npm ci
+COPY frontend/ ./
+RUN npx shadow-cljs release app
+
+FROM python:3.12-slim-bookworm
+
+ENV PYTHONDONTWRITEBYTECODE=1 \
+    PYTHONUNBUFFERED=1 \
+    DJANGO_DEBUG=0 \
+    DJANGO_DB_PATH=/data/db.sqlite3 \
+    DJANGO_BLOB_ROOT=/data/blobs
+
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends ffmpeg \
+    && rm -rf /var/lib/apt/lists/* \
+    && useradd --create-home --shell /usr/sbin/nologin app
+
+WORKDIR /app
+COPY requirements.txt ./
+RUN pip install --no-cache-dir -r requirements.txt
+COPY . ./
+COPY --from=frontend /app/static/arthur/js/ ./static/arthur/js/
+RUN python manage.py collectstatic --noinput \
+    && mkdir -p /data \
+    && chown -R app:app /app /data
+
+USER app
+EXPOSE 8000
+CMD ["sh", "-c", "python manage.py migrate --noinput && exec gunicorn server.wsgi:application --bind 0.0.0.0:8000 --workers 1 --threads 4 --timeout 120"]