Introduce new build configuration "64bit-no-nan-tagging" for both 64-bit and 32-bit platforms, defining WREN_NAN_TAGGING=0 to disable NaN tagging in the Wren CLI. Update Makefiles, premake5.lua, and Visual Studio solution/project files to support the new config with appropriate compiler flags, linker settings, and platform-specific defines (e.g., _GNU_SOURCE on Linux, _DARWIN_* on macOS).
Add initial build system configuration for the wren-cli command-line tool,
including a premake5.lua script defining workspace, project, and dependency
paths for libuv and wren, plus generated Visual Studio 2019 solution and
project files with Debug/Release and 32bit/64bit platform support.
