Adds automatic detection of Homebrew-installed googletest to support
offline/sandboxed builds (e.g., Claude Code, restricted networks).
Changes:
- Add Homebrew detection logic to cmake/dependencies/testing.cmake
- Check /opt/homebrew/opt/googletest and /usr/local/opt/googletest
- Use brew --prefix googletest for dynamic detection
- Create target aliases (gtest -> GTest::gtest) for compatibility
- Only fetch from GitHub if no local installation found
- Update macOS build docs with yaml-cpp and googletest installation
Pattern mirrors existing yaml.cmake implementation. Complements the
pre-existing yaml-cpp Homebrew fallback to minimize network dependencies.
Tested with: brew install googletest (1.17.0, 2.4MB)
Co-Authored-By: Claude <noreply@anthropic.com>
405b542e98