Add Drupal headless stack with Next.js frontend

- Add Next.js frontend service (nextjs) with Dockerfile and source
- Update docker-compose.yml: image names, Drupal 11.3.3, nextjs service
- Add docker-compose.override.yml.disabled for dev hot-reload
- Add install-headless-modules.sh for OAuth/JSON:API module setup
- Add README.md with full setup and configuration guide
- Update nginx/Dockerfile and nginx.conf.template for cms. subdomain
- Update drupal/Dockerfile PHP-FPM build args
- Gitignore **/.vscode/ to prevent IDE workspace files from being tracked

drupal/nextjs/Dockerfile

@@ -0,0 +1,61 @@
+# Stage 0: Development (bind-mount source, run next dev).
+FROM node:22-alpine AS development
+RUN apk add --no-cache libc6-compat
+WORKDIR /app
+COPY package.json package-lock.json* ./
+RUN npm ci || npm install
+COPY . .
+EXPOSE 3000
+ENV PORT=3000
+ENV HOSTNAME="0.0.0.0"
+ENV NODE_ENV=development
+# WATCHPACK_POLLING helps with bind mounts on some file systems.
+ENV WATCHPACK_POLLING=true
+ENTRYPOINT ["sh", "-c", "[ -d node_modules/.bin ] || npm install; exec npm run dev"]
+
+# Stage 1: Install dependencies.
+FROM node:22-alpine AS deps
+RUN apk add --no-cache libc6-compat
+WORKDIR /app
+COPY package.json package-lock.json* ./
+RUN npm ci || npm install
+
+# Stage 2: Build the application.
+FROM node:22-alpine AS builder
+WORKDIR /app
+COPY --from=deps /app/node_modules ./node_modules
+COPY . .
+
+# Build arguments for environment variables needed at build time.
+ARG NEXT_PUBLIC_DRUPAL_BASE_URL
+ARG DRUPAL_CLIENT_ID
+ARG DRUPAL_CLIENT_SECRET
+ARG DRUPAL_OAUTH_SCOPE
+ENV NEXT_PUBLIC_DRUPAL_BASE_URL=${NEXT_PUBLIC_DRUPAL_BASE_URL}
+ENV DRUPAL_CLIENT_ID=${DRUPAL_CLIENT_ID}
+ENV DRUPAL_CLIENT_SECRET=${DRUPAL_CLIENT_SECRET}
+ENV DRUPAL_OAUTH_SCOPE=${DRUPAL_OAUTH_SCOPE}
+
+RUN npm run build
+
+# Stage 3: Production runner.
+FROM node:22-alpine AS runner
+WORKDIR /app
+
+ENV NODE_ENV=production
+
+RUN addgroup --system --gid 1001 nodejs
+RUN adduser --system --uid 1001 nextjs
+
+# Copy standalone output.
+COPY --from=builder /app/public ./public
+COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
+COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
+
+USER nextjs
+
+EXPOSE 3000
+ENV PORT=3000
+ENV HOSTNAME="0.0.0.0"
+
+CMD ["node", "server.js"]