chore: import upstream snapshot with attribution

examples/integrations/ms-agent-framework-dotnet/docker/Dockerfile.app

@@ -0,0 +1,45 @@
+# Dockerfile for the MS Agent Framework Next.js frontend.
+# Builds standalone Next.js output from the root-level frontend.
+FROM node:20-slim AS builder
+
+WORKDIR /app
+
+# Copy package files and install
+COPY package.json pnpm-lock.yaml* ./
+RUN npm install --ignore-scripts
+
+# Copy source code
+COPY src/ ./src/
+COPY public/ ./public/
+COPY next.config.ts tsconfig.json postcss.config.mjs ./
+COPY next-env.d.ts ./
+
+# Add standalone output mode for Docker
+RUN node -e "\
+  const fs = require('fs'); \
+  const f = 'next.config.ts'; \
+  let c = fs.readFileSync(f, 'utf8'); \
+  if (!c.includes('standalone')) { \
+    c = c.replace('serverExternalPackages:', \"output: 'standalone',\\n  serverExternalPackages:\"); \
+    fs.writeFileSync(f, c); \
+  }"
+
+# Build
+RUN npm run build
+
+# Production stage
+FROM node:20-slim AS runner
+
+WORKDIR /app
+
+ENV NODE_ENV=production
+ENV PORT=3000
+ENV HOSTNAME=0.0.0.0
+
+COPY --from=builder /app/.next/standalone ./
+COPY --from=builder /app/.next/static ./.next/static
+COPY --from=builder /app/public ./public
+
+EXPOSE 3000
+
+CMD ["node", "server.js"]