- Add docker/setup-qemu-action@v3 to docker-publish.yml (was missing,
causing multi-platform builds to hang indefinitely)
- Add platforms: linux/amd64,linux/arm64 to build-push-action step
- Optimize Dockerfile with --platform=$BUILDPLATFORM on builder stages
so TypeScript compilation runs at native amd64 speed; only the lean
npm ci --omit=dev step runs under QEMU in the final stage, compiling
the three native modules (bcrypt, better-sqlite3, node-pty) for the
correct target architecture — reduces arm64 build time from 6+ hours
to ~15-30 minutes