Tracking Issue: Running Tasks on Host/Native #2706

This is a tracking issue to discuss the capability to run Hubris tasks natively on the host, as native processes.

Rather than emulating at the cortex-m level, we may want to natively compile Hubris tasks and the kernel for a host, such as x86_64/aarch64 Linux/MacOS.

There are currently PRs open to make this possible (more soon):

• abi/kern/userlib: Use usize-like data for addr+len #2703
• kernel: Introduce Arch trait #2704
• userlib: Introduce Arch trait #2705
• macos: Emit reasonable linker section names on macOS idolatry#78

And here are some diagrams that help explain where we are, and where we want to be:

Today's kernel/userspace interaction (on cortex-m)

Post 2703/2704/2705 (on cortex-m)

The shiny future (on native/host)