[Feature] CI: Multi-arch native binaries (macOS + linux/arm64)

[alxsuv]

Current state

README.md:317 — "Pre-built server binaries are Linux x86_64 only. macOS and ARM targets are planned."

Targets

• linux-x86_64 (existing)
• linux-aarch64
• darwin-x86_64
• darwin-aarch64

Approach

GitHub Actions matrix — one job per (os, arch). GraalVM native-image cross-compilation is unreliable; build natively on each runner.

Target	Runner
linux-x86_64	ubuntu-latest
linux-aarch64	ubuntu-24.04-arm
darwin-x86_64	macos-13
darwin-aarch64	macos-latest (Apple Si)

Implementation

1. .github/workflows/release.yml — matrix job:
   • setup-java → distribution: graalvm-community, java-version: 25.
   • ./gradlew :hensu-server:build -Dquarkus.package.type=native -Dquarkus.native.container-build=false.
   • Artifact name: hensu-server-${version}-${os}-${arch}.
   • actions/upload-artifact per leg.
2. Release job (needs: all matrix legs) — download artifacts, gh release upload to tag.
3. shasum -a 256 per binary → publish SHA256SUMS.
4. README.md:317 — replace Linux-only note with a download table for the four targets.

Native-image gotchas

• aarch64 musl static linking unsupported → dynamic libc on Linux ARM.
• reflect-config.json validated per target (missing entries surface only at target runtime).
• macOS Xcode CLT preinstalled on GH runners — no extra setup.

Out of scope

• Windows binaries.
• Homebrew / apt / Docker manifest list.
• macOS code signing + notarization (Gatekeeper warning remains until addressed).

Acceptance

• Tagging vX.Y.Z produces 4 binaries + SHA256SUMS on the GH release.
• README.md install section links each target.
• CI time per leg < 25 min.