The aarch64 loader link step hardcoded the unversioned "lld-link", which
isn't on PATH by default on this Debian/Ubuntu setup (the package only
installs lld-link-18 under /usr/bin; unversioned lld-link lives under
/usr/lib/llvm-18/bin). CI worked around this with an explicit PATH prefix
in the workflow; a local build without that PATH override failed. Now
auto-detects whichever name resolves, falling back to the versioned name.
Verified: aarch64 builds clean with the default PATH.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Kernel version only — the embedded StarForth engine version (3.1.0) is left
alone since it tracks a vendored copy that has genuinely diverged from the
standalone StarForth repo, not something to auto-sync. Verified builds on
amd64, aarch64, and riscv64.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>