[sn32] Complete flashing support

[dexter93]

Description

Sonixflasher is now available in every platform

Windows -> https://packages.msys2.org/base/mingw-w64-sonixflasher ( binary)
MacOS -> https://github.com/SonixQMK/homebrew-sonixqmk/pkgs/container/sonixqmk%2Fsonixflasher ( binary)
Linux -> https://github.com/SonixQMK/SonixFlasherC/releases ( source)

That means we can use it in the qmk repo.
Also provide the necessary hooks for qmk setup so that it's automatically bundled.

Flash options

• precompiled .bin qmk flash keyboard_keymap.bin
• on the fly compile and flash qmk flash --keyboard <keyboard_dir> --keymap <keymap>

And in case a GUI is preferred, see SonixQMK/qmk_toolbox

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout/userspace (addition or update)
• Documentation

Issues Fixed or Closed by This PR

Checklist

• My code follows the code style of this project: C, Python
• I have read the PR Checklist document and have made the appropriate changes.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[dexter93]

note: sonixflasher can't be added to qmk doctor at this point, since CLI CI tests will fail against the docker container ghcr.io/qmk/qmk_base_container

It is left up to the user to confirm the flasher is present and up to date