Add StartOS 0.4.0 packaging

Dockerfile

@@ -0,0 +1,62 @@
+# ─────────────────────────────────────────────────────────
+#  YouTube Summarizer — StartOS 0.4 Docker image
+#
+#  Includes: Node.js 20, Python 3, yt-dlp, ffmpeg
+#
+#  Uses Debian slim (not Alpine) because:
+#  - yt-dlp's --impersonate chrome requires curl_cffi (compiled C extension)
+#  - curl_cffi's prebuilt wheels target glibc, not musl
+#  - Debian is more reliable for pip-installed packages with C deps
+# ─────────────────────────────────────────────────────────
+
+# ── Stage 1: Install Node.js dependencies ──────────────────
+FROM node:20-slim AS builder
+
+WORKDIR /app/server
+COPY server/package.json server/package-lock.json* ./
+RUN npm ci --production --ignore-scripts 2>/dev/null || npm install --production --ignore-scripts
+
+# ── Stage 2: Final runtime image ───────────────────────────
+FROM node:20-slim AS runner
+
+WORKDIR /app
+
+# Install runtime dependencies:
+#   - dumb-init: proper PID 1 signal handling in containers
+#   - curl: health checks + yt-dlp binary downloads
+#   - python3 + pip: yt-dlp installation and updates
+#   - ffmpeg: audio extraction, splitting, and duration detection
+#   - ca-certificates: HTTPS for YouTube/Gemini API calls
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    dumb-init \
+    curl \
+    python3 \
+    python3-pip \
+    python3-venv \
+    ffmpeg \
+    ca-certificates \
+  && rm -rf /var/lib/apt/lists/* \
+  && pip3 install --break-system-packages yt-dlp curl_cffi \
+  && yt-dlp --version
+
+# Copy Node.js app from builder
+COPY --from=builder /app/server/node_modules ./server/node_modules/
+COPY server/package.json ./server/
+COPY server/index.js ./server/
+COPY public/ ./public/
+COPY assets/ ./assets/
+
+# Copy entrypoint scripts
+COPY docker_entrypoint.sh /usr/local/bin/docker_entrypoint.sh
+RUN chmod +x /usr/local/bin/docker_entrypoint.sh
+
+# Create persistent data mount point
+RUN mkdir -p /data
+
+ENV NODE_ENV=production \
+    PORT=3001 \
+    DATA_DIR=/data
+
+EXPOSE 3001
+
+ENTRYPOINT ["dumb-init", "--", "/usr/local/bin/docker_entrypoint.sh"]