hikari wayland compositor (https://hikari.acmelabs.space)

#4Feature: support specifying keyboard layout by full xkb file

I have a custom xkb symbols file for my personal layout that's been tweaked over the years. Now that I've been trying out wayland compositors a bit, it'd be great to be able to use this layout rather than one of the standard system-wide ones, ideally without having to copy mine over to the standard ones.

I found in Sway that it offers an 'xkb_file' input command that lets you specify a full xkb file containing the combination of rules, model, layout, variant and options, which solves this nicely for me! It'd be nice with similar support in hikari, either via an environment variable or as part of the 'input' section.

The Sway manual also suggests that such a combined xkb file can be produced on a running system (also in X11 too) via 'xkbcomp $DISPLAY keymap.xkb', which is helpful to provide in the manual if an option for this is added!