[phaedrus-on-git]

Summary

• updates the container publish workflow actions to current major versions
• pins Docker Buildx to moby/buildkit:v0.31.0 instead of the current default v0.32.2
• addresses the scheduled multi-arch publish failure reported in Build failed: 2026-09-28 #64, where the arm64 Go tool install failed under BuildKit v0.32.2 with a proxy.golang.org HTTP/2 stream INTERNAL_ERROR

Validation

• git diff --check origin/main...HEAD
• yq e .name .github/workflows/build.yml
• verified the Set up Docker Buildx step renders driver-opts: image=moby/buildkit:v0.31.0

Fixes #64