fix: Docker one-click deployment — all deps bundled, native modules, health check

- Multi-stage build: builder installs backend + frontend deps, compiles
- Production stage: npm ci --production rebuilds native modules (opus, sqlite3)
- FFmpeg bundled via ffmpeg-static (no apt install ffmpeg)
- .dockerignore prevents node_modules/dist from being copied
- docker-compose uses host network for TS3 UDP connectivity
- Named volume for persistent data
- Health check endpoint

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/docker/Dockerfile

@@ -1,24 +1,63 @@
+# ==========================================
+# TSMusicBot Docker Image
+# One-click deployment — all dependencies included
+# ==========================================
+
+# --- Stage 1: Build backend + frontend ---
 FROM node:20-slim AS builder
 
-WORKDIR /app
-COPY package*.json ./
-RUN npm ci
-
-COPY . .
-RUN npm run build
-
-FROM node:20-slim
-
-RUN apt-get update && apt-get install -y --no-install-recommends ffmpeg && \
+# Install build tools for native modules (opus, better-sqlite3)
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    python3 make g++ && \
     rm -rf /var/lib/apt/lists/*
 
 WORKDIR /app
+
+# Install backend dependencies
+COPY package*.json ./
+RUN npm ci
+
+# Install frontend dependencies
+COPY web/package*.json ./web/
+RUN cd web && npm ci
+
+# Copy source and build
+COPY . .
+RUN npm run build
+
+# --- Stage 2: Production image ---
+FROM node:20-slim
+
+# Install only runtime native build tools (needed for native module rebuild)
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    python3 make g++ && \
+    rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# Copy built output
 COPY --from=builder /app/dist ./dist
 COPY --from=builder /app/web/dist ./web/dist
 COPY --from=builder /app/package*.json ./
-RUN npm ci --production
 
-EXPOSE 3000
+# Install production dependencies (includes ffmpeg-static, opus, sqlite3)
+# These need to compile native addons inside the container
+RUN npm ci --production && npm cache clean --force
+
+# Remove build tools to reduce image size
+RUN apt-get purge -y python3 make g++ && apt-get autoremove -y && \
+    rm -rf /var/lib/apt/lists/*
+
+# FFmpeg is bundled via ffmpeg-static — no system ffmpeg needed
+
+# Data directory for database, cookies, logs
+RUN mkdir -p /app/data
 VOLUME ["/app/data"]
 
+EXPOSE 3000
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s \
+    CMD node -e "fetch('http://localhost:3000/api/health').then(r=>r.ok?process.exit(0):process.exit(1)).catch(()=>process.exit(1))"
+
 CMD ["node", "dist/index.js"]