chore: add coolify-ready docker packaging and deployment env template

Dockerfile

@@ -0,0 +1,19 @@
+FROM node:22-alpine
+
+WORKDIR /app
+
+ENV NODE_ENV=production
+ENV PORT=3000
+ENV STATE_FILE_PATH=/data/state.json
+
+COPY package.json ./
+COPY src ./src
+COPY README.md ./README.md
+COPY spec.md ./spec.md
+
+EXPOSE 3000
+VOLUME ["/data"]
+
+HEALTHCHECK --interval=30s --timeout=5s --retries=3 CMD node -e "fetch('http://127.0.0.1:'+process.env.PORT+'/health').then((r)=>process.exit(r.ok?0:1)).catch(()=>process.exit(1))"
+
+CMD ["node", "src/server.js"]