port: existing snippets to MacOS

[PhantomCloak]

Summary

This PR ports the existing PhysX snippets to MacOS. I tested these changes on my M1 Mac, where all snippets ran successfully without any issues further feedbacks & validations are welcome.

Key changes

• The Werror flag has been taken out from the compiler options, for MacOS due to several warnings found in the source code while trying to compile on clang since these warning not within scope of this PR making this change will solve the issue with minimal impact.
• SnippetRender.cpp Now it calls glutCreateWindow before initialising the GLFontRenderer with gTexter.init(). This adjustment solves an issue where the GL context wasn't properly initialised until glutCreateWindow was called which previously causes segfault at GLFontRenderer::init -> glGenTextures(1, (GLuint*)&m_textureObject);.
• Added several CMake files to compile snippets under the physx/snippets/compiler/cmake/mac