feat: add Docker deployment support

- Add multi-stage Dockerfile for Next.js standalone build
- Add docker-compose.yml with app and MySQL 8.0 services
- Add .dockerignore for optimized builds
- Update next.config.ts with standalone output

Dockerfile

@@ -0,0 +1,43 @@
+# Dockerfile for Recipe Translation Tool
+# Stage 1: Builder
+FROM node:20-alpine AS builder
+
+WORKDIR /app
+
+# Copy package files
+COPY package.json pnpm-lock.yaml ./
+
+# Install dependencies
+RUN corepack enable && pnpm install --frozen-lockfile
+
+# Copy source code
+COPY . .
+
+# Build the application
+RUN pnpm build
+
+# Stage 2: Runner
+FROM node:20-alpine AS runner
+
+WORKDIR /app
+
+ENV NODE_ENV=production
+
+# Create non-root user
+RUN addgroup --system --gid 1001 nodejs && \
+    adduser --system --uid 1001 nextjs
+
+# Copy built application
+COPY --from=builder /app/public ./public
+COPY --from=builder /app/.next/standalone ./
+COPY --from=builder /app/.next/static ./.next/static
+
+# Set ownership
+USER nextjs
+
+EXPOSE 3000
+
+ENV PORT=3000
+ENV HOSTNAME="0.0.0.0"
+
+CMD ["node", "server.js"]