added docker files and compose

backend/Dockerfile

@@ -1,14 +1,14 @@
 FROM node:20-alpine
 
+# better-sqlite3 needs build tools
+RUN apk add --no-cache python3 make g++
+
 WORKDIR /app
-
 COPY package.json package-lock.json* ./
-RUN npm ci --production
-
+RUN npm install --production
 COPY . .
 
 RUN mkdir -p /app/data /app/uploads
 
 EXPOSE 4000
-
 CMD ["node", "server.js"]