fix: add Dockerfile + standalone output for Coolify deploy (FIBEROPS-249)

Dockerfile

@@ -0,0 +1,22 @@
+FROM node:22-alpine AS builder
+WORKDIR /app
+
+COPY package*.json ./
+RUN npm ci
+
+COPY . .
+ENV NEXT_TELEMETRY_DISABLED=1
+RUN npm run build
+
+FROM node:22-alpine AS runner
+WORKDIR /app
+ENV NODE_ENV=production
+ENV NEXT_TELEMETRY_DISABLED=1
+
+COPY --from=builder /app/.next/standalone ./
+COPY --from=builder /app/.next/static ./.next/static
+COPY --from=builder /app/public ./public
+
+EXPOSE 3000
+ENV PORT=3000
+CMD ["node", "server.js"]