feat(frontend): Add Docker containerization support for development and production

Implement complete Docker setup for Next.js 16 frontend with multi-stage builds,
hot reload support, and production optimizations.

Changes:
- Add Dockerfile with multi-stage build (deps, builder, development, production)
- Add .dockerignore to exclude unnecessary files from Docker context
- Add .env.local.example template for environment configuration
- Update next.config.ts with standalone output for production builds
- Add Docker convenience scripts to package.json for easy container management
- Support hot reload in development with volume mounts
- Use Node.js 20 Alpine for smaller image size
- Implement security best practices (non-root user in production)

Technical Details:
- Development stage: Full source mounted with hot reload via Turbopack
- Production stage: Standalone build with optimized static assets
- Image size: ~1.17GB (development), smaller for production
- Port: 3000 (maps to container port 3000)

Testing:
- Docker build verified for development target
- Container startup successful with Next.js 16.0.1
- HTTP 200 response confirmed on localhost:3000
- Hot reload functional with volume mounts

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Dockerfile

@@ -0,0 +1,88 @@
+# ============================================
+# Stage 1: Dependencies Installation
+# ============================================
+FROM node:20-alpine AS deps
+WORKDIR /app
+
+# Install libc6-compat for compatibility
+RUN apk add --no-cache libc6-compat
+
+# Copy dependency files
+COPY package.json package-lock.json* ./
+
+# Install dependencies with legacy peer deps flag for Next.js 16
+RUN npm ci --legacy-peer-deps
+
+# ============================================
+# Stage 2: Build Stage
+# ============================================
+FROM node:20-alpine AS builder
+WORKDIR /app
+
+# Copy dependencies from deps stage
+COPY --from=deps /app/node_modules ./node_modules
+
+# Copy all source files
+COPY . .
+
+# Disable Next.js telemetry
+ENV NEXT_TELEMETRY_DISABLED=1
+
+# Build the application
+RUN npm run build
+
+# ============================================
+# Stage 3: Development Environment (Default)
+# ============================================
+FROM node:20-alpine AS development
+WORKDIR /app
+
+# Set environment variables
+ENV NODE_ENV=development
+ENV NEXT_TELEMETRY_DISABLED=1
+
+# Install libc6-compat for compatibility
+RUN apk add --no-cache libc6-compat curl
+
+# Copy dependencies from deps stage
+COPY --from=deps /app/node_modules ./node_modules
+
+# Copy source code (will be overridden by volume mount in docker-compose)
+COPY . .
+
+# Expose Next.js default port
+EXPOSE 3000
+
+# Use turbo mode for faster development
+CMD ["npm", "run", "dev"]
+
+# ============================================
+# Stage 4: Production Environment
+# ============================================
+FROM node:20-alpine AS production
+WORKDIR /app
+
+# Set environment variables
+ENV NODE_ENV=production
+ENV NEXT_TELEMETRY_DISABLED=1
+
+# Install libc6-compat
+RUN apk add --no-cache libc6-compat
+
+# Create non-privileged user for security
+RUN addgroup --system --gid 1001 nodejs && \
+    adduser --system --uid 1001 nextjs
+
+# Copy build artifacts from builder stage
+COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
+COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
+COPY --from=builder --chown=nextjs:nodejs /app/public ./public
+
+# Switch to non-privileged user
+USER nextjs
+
+# Expose port
+EXPOSE 3000
+
+# Start the standalone server
+CMD ["node", "server.js"]