Build a portable static binary

The CI and release workflows build musl targets natively for x86_64 and aarch64.

Install musl tools and build:

sudo apt-get update
sudo apt-get install -y musl-tools
rustup target add x86_64-unknown-linux-musl
cargo build --release --locked --target x86_64-unknown-linux-musl -p tailor

Stage and verify:

mkdir -p dist
install -Dm755 target/x86_64-unknown-linux-musl/release/tailor \
  dist/tailor-x86_64-unknown-linux-musl
( cd dist && sha256sum tailor-x86_64-unknown-linux-musl > tailor-x86_64-unknown-linux-musl.sha256 )
file dist/tailor-x86_64-unknown-linux-musl

The workflow accepts static-pie linked or statically linked. tailor uses Rustls-based dependencies, so the release binary is not dynamically linked to glibc or OpenSSL. Users still need Docker daemon access at runtime.