Add hostmcu Workflow

[mkuf]

for #72

Adds:

• new file docker-compose.extra.hostmcu.yaml
• new build targets build-hostmcu and hostmcu to the main klipper Dockerfile
• Info about hostmcu tags to klipper Image readme
• build config for the klipper_mcu binary

Changes:

• renames mcu tag to tools for better destinction and allow a more broader use of the image, not only for mcu related tasks
• adds the klipper user to group tty within the Image
• replaces mcu with tools tags in klipper Image readme

ToDo:

• [x] Update the main Readme on how to set up the hostprocess
• [x] rebase and simplify after #78 has been merged

[mkuf]

Rebase was done and profile for hostmcu prepared.
Github Image build action runs in a timeout at 6hrs, which should not take much longer than before.
Needs investigating.

[mkuf]

With the renaming of the mcu target to tools, the build script attempts to build a lot more images then expected.

no such manifest: docker.io/mkuf/klipper:645a1b8
## ## Building latest Image mkuf/klipper:645a1b8 
## ## Image mkuf/klipper:v0.9.1 already exists, nothing to do. 
## ## Image mkuf/klipper:v0.10.0 already exists, nothing to do. 
## ## Image mkuf/klipper:v0.11.0 already exists, nothing to do. 
no such manifest: docker.io/mkuf/klipper:645a1b8-tools
## ## Building latest Image mkuf/klipper:645a1b8-tools 
no such manifest: docker.io/mkuf/klipper:v0.9.1-tools
## ## Building Image for tagged release mkuf/klipper:v0.9.1-tools 
no such manifest: docker.io/mkuf/klipper:v0.10.0-tools
## ## Building Image for tagged release mkuf/klipper:v0.10.0-tools 
no such manifest: docker.io/mkuf/klipper:v0.11.0-tools
## ## Building Image for tagged release mkuf/klipper:v0.11.0-tools 
no such manifest: docker.io/mkuf/klipper:645a1b8-hostmcu
## ## Building latest Image mkuf/klipper:645a1b8-hostmcu 
no such manifest: docker.io/mkuf/klipper:v0.9.1-hostmcu
## ## Building Image for tagged release mkuf/klipper:v0.9.1-hostmcu 
no such manifest: docker.io/mkuf/klipper:v0.10.0-hostmcu
## ## Building Image for tagged release mkuf/klipper:v0.10.0-hostmcu 
no such manifest: docker.io/mkuf/klipper:v0.11.0-hostmcu
## ## Building Image for tagged release mkuf/klipper:v0.11.0-hostmcu 

As github actions are cpu limited, I'll run the build for those images on my local machine to speed things up.
When the Images are pushed to dockerhub, the builds via github actions should work fine.

[mkuf]

Images have been pushed from my local machine and a manually triggered github action created the latest Images necessary for testing: https://github.com/mkuf/prind/actions/runs/5226594730