Improved MacOS support

This MR adds improves to support for mac os (#29 (closed))

• GH actions: build for mac os
• Use glfw_async

This workarounds some crashes, but introduces some even worse.

Tasks:

• Fix running with eros
• Remove -XstartOnFirstThread
• remove ASB warning (not possible)
• Fix black textures (happens because on my device the depth of glTexImage3D is limited to 512, I need ~1600)
• Multiple connections (untested)
• Window/dock icon (not possible with glfw, see https://github.com/glfw/glfw/issues/2041)