Adds x86_64-unknown-linux-musl, aarch64-unknown-linux-gnu, and
aarch64-unknown-linux-musl to the napi build targets so
@firecrawl/pdf-inspector works on Alpine and ARM64 Linux deployments.
- gnu arm64 cross-compiles with --use-napi-cross (old-glibc sysroot),
musl targets with -x (zig + cargo-zigbuild), per the napi-rs template
- new platform packages carry npm libc metadata (glibc/musl)
- smoke-test job runs napi/test.mjs on all six targets before publish
(Alpine containers for musl, ubuntu-24.04-arm runners for ARM64)
- bump to 1.12.0 to trigger publishing of all platform packages
Closes#216