feat(infra): add hub service — Docker, Traefik, CI/CD

- Add infra/docker/hub.Dockerfile (Next.js multi-stage build)
- Add infra/compose/hub.yml with app-shared-net
- Add Traefik route for hub.asepharyana.{my,web}.id → hub:3000
- Update docker-build-push.yml: path detection, matrix build, dispatch, manifest
- Update deploy-docker.yml: include hub.yml in ALL_COMPOSE_FILES
- Update update-submodule.yml: allow hub service
- Update docs/ARCHITECTURE.md

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

infra/docker/hub.Dockerfile

@@ -0,0 +1,20 @@
+# ── Build stage ──
+FROM node:22-alpine AS builder
+WORKDIR /app
+COPY apps/hub/package.json apps/hub/bun.lock ./
+RUN npm install --frozen-lockfile
+COPY apps/hub .
+RUN npm run build
+
+# ── Runtime ──
+FROM node:22-alpine AS runtime
+RUN addgroup -S appgroup && adduser -S appuser -G appgroup
+WORKDIR /app
+COPY --from=builder /app/.next ./.next
+COPY --from=builder /app/node_modules ./node_modules
+COPY --from=builder /app/public ./public
+COPY --from=builder /app/package.json ./
+USER appuser
+EXPOSE 3000
+ENV PORT=3000 NODE_ENV=production
+CMD ["npm", "run", "start"]