The -Wl,-z,relro and -Wl,-z,now flags are ELF-specific and not
supported by macOS's linker. Guard them with if(NOT APPLE).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Remove legacy build files (Makefile, makefile.unix/mingw/osx,
triangles-qt.pro) and replace with CMake build system. Includes
find modules for all dependencies, LevelDB bundled build, and
updated CI workflow for CMake + Ninja on all platforms.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
sami7777