Replace Buildroot toolchain references with the new docker-arm64 setup in CLAUDE.md, TOOLCHAIN.md, and the changelog. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Replace Buildroot toolchain references with the new docker-arm64 setup in CLAUDE.md, TOOLCHAIN.md, and the changelog. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>