Top-level BUILD.md so users see the dependency list (libz3-dev,
libclang-dev, llvm-dev, etc.) without spelunking docs/. Lists apt
package names for Ubuntu/Debian, dnf names for Fedora/RHEL, and
brew names for macOS — kept in sync with docker/Dockerfile.linux-
validate, which is the executable spec.
- README points at BUILD.md instead of docs/BUILDING.md.
- docs/BUILDING.md trimmed to radare2 vendoring notes only (the
topic that didn't belong in a top-level quick-start).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>