user/wlr-which-key: new package

[0xF32]

Description

wlr-which-key is a configurable tool to show keymaps onto the screen for wlroots-based compositors. It is very fast and minimal.

Checklist

Before this pull request is reviewed, certain conditions must be met.

The following must be true for all changes:

• I have read CONTRIBUTING.md
• I acknowledge that overtly not following the above or the below will result in my pull request getting closed

The following must be true for template/package changes:

• I have read Packaging.md
• I have built and tested my changes on my machine

The following must be true for new package submissions:

• I will take responsibility for my template and keep it up to date

[0xF32]

This package template was previously checked by q66 and has not changed since.
Previous pr: #5545
I hope that I can be positive despite my mistakes in communication.