A C++ toolchain from 357 bytes, in Bazel

A Bazel C++ toolchain has been built whose entire ancestry traces back to the 357-byte stage0 seed program. Starting from that minimal hex seed, the toolchain bootstraps all the way up to a working C++ compiler, enabling hermetic builds without relying on any prebuilt binaries. The toolchain successfully compiles Abseil and GoogleTest from the Bazel Central Registry without patches, passing all 236 tests. An audit report using Bazel aspects verifies that every build action uses only programs built within the repository, with only two audited seed binaries as exceptions (the hex0 seed itself and the system shell). This approach mirrors what Guix and NixOS have done to minimize binary seeds and improve build reproducibility.