Add Dockerized FastNext stack template with backend and frontend

Implemented a full-stack template combining Next.js (frontend), FastAPI (backend), and PostgreSQL. Included Docker configurations for development and production, environment file templates, Makefile commands, and initial setup for database migrations and builds. The stack is production-ready and supports hot-reloading for local development.

frontend/Dockerfile

@@ -0,0 +1,36 @@
+# Stage 1: Dependencies
+FROM node:20-alpine AS deps
+WORKDIR /app
+COPY package.json package-lock.json ./
+RUN npm ci
+
+# Stage 2: Builder
+FROM node:20-alpine AS builder
+WORKDIR /app
+COPY --from=deps /app/node_modules ./node_modules
+COPY . .
+ENV NEXT_TELEMETRY_DISABLED 1
+RUN npm run build
+
+# Stage 3: Runner
+FROM node:20-alpine AS runner
+WORKDIR /app
+
+ENV NODE_ENV production
+ENV NEXT_TELEMETRY_DISABLED 1
+
+RUN addgroup --system --gid 1001 nodejs
+RUN adduser --system --uid 1001 nextjs
+
+COPY --from=builder /app/public ./public
+COPY --from=builder /app/.next/standalone ./
+COPY --from=builder /app/.next/static ./.next/static
+
+USER nextjs
+
+EXPOSE 3000
+
+ENV PORT 3000
+ENV HOSTNAME "0.0.0.0"
+
+CMD ["node", "server.js"]