ci: report per-route JavaScript budgets from Docker build

Dockerfile

@@ -37,7 +37,8 @@ RUN --mount=type=cache,target=/app/.next/cache \
     DATABASE_URL="mysql://build:[email protected]:9/build" \
     HOTEL_NAME="Build fixture" APP_URL="http://localhost:3002" \
     AUTH_SECRET="build-fixture-not-for-runtime-use-000000000000" \
-    pnpm run build
+    pnpm run build \
+    && PERFORMANCE_COMMIT_SHA="$NEXT_DEPLOYMENT_ID" node scripts/performance-report.mjs --output-dir build-reports
 
 FROM node:26.8.2-alpine AS runner
 ARG NEXT_DEPLOYMENT_ID="unknown"
@@ -54,6 +55,7 @@ RUN apk add --no-cache tini curl \
 COPY --from=builder --chown=nextjs:nextjs /app/public ./public
 COPY --from=builder --chown=nextjs:nextjs /app/.next/standalone ./
 COPY --from=builder --chown=nextjs:nextjs /app/.next/static ./.next/static
+COPY --from=builder --chown=nextjs:nextjs /app/build-reports ./build-reports
 COPY --from=builder --chown=nextjs:nextjs /app/drizzle/migrations ./drizzle/migrations
 COPY --chown=nextjs:nextjs scripts/docker-start.mjs ./docker-start.mjs
 USER nextjs