🧵 POSIX threading support

[liam-teale]

Overview

FreeRTOS-POSIX should be added as a dependency, to gain support for POSIX threading

Motivation

This will enable users and library developers to use features like std::thread, significantly improving UX and DX. This also helps facilitate the decoupling of freeRTOS in future

Implementation

This can be added as a git submodule