Cross-platform binary releases for Zig 0.15.2 with Xtensa support

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Goal

Build and release pre-compiled Zig 0.15.2 binaries with Xtensa (ESP32) support for multiple platforms.

Target Platforms

• aarch64-macos-none - macOS Apple Silicon
• x86_64-macos-none - macOS Intel
• x86_64-linux-gnu - Linux x86_64
• aarch64-linux-gnu - Linux ARM64

Progress

Phase 1: Bootstrap Script Improvements ✅

• Upgrade to Zig 0.15.2
• Support Codeberg git clone (ziglang migrated from GitHub)
• Add clean command
• Support per-target build directories (.build-<target>-<mcpu>)
• Fix patch application (patch -p1 instead of git apply)
• Fix build script call (./build instead of ./build.sh)

Phase 2: macOS ARM64 Build & Test ✅

• Bootstrap Zig 0.15.2 for aarch64-macos-none
• Verify Xtensa architecture support
• Compile example project (led_strip_flash)
• Flash to ESP32S3
• Verify serial output - LED toggling works!

Phase 3: Additional Platform Builds

• Build x86_64-macos-none
• Build x86_64-linux-gnu (cross-compile from macOS)
• Build aarch64-linux-gnu (cross-compile from macOS)

Phase 4: Release

• Package all binaries as .tar.xz
• Create GitHub Release with gh release create
• Add SHA256 checksums

Notes

• Linux cross-compilation from macOS may have challenges with libstdc++ requirements
• Consider using Docker/Podman for Linux builds if native cross-compilation fails