Update for wlroots 0.18

[jchv]

Things have fallen a bit out of date. I hope it isn't a big problem that I've grouped a lot of stuff into this PR. To try to make it a bit cleaner it is at least broken up into commits.

The broad strokes of this are:

• Fix two minor typos (handleOuptuDestroy -> handleOutputDestroy, PrefferedMode -> PreferredMode)
• Delete obsolete wlroots APIs (mainly: the pending state APIs in wlr_output_* and the non-renderpass APIs in wlr_renderer_*
• Update bindings for wlroots 0.18:
  • Add RenderPass API
  • Add Display argument to NewOutputLayout and CreateGlobal
  • Add relative direction to NotifyPointerAxis
  • Remove Vendor/Product from InputDevice, since it's not supported anymore
  • Add RelativeDirection enum
  • Switch values of AxisSource to use wl_pointer_axis enum
  • Add BeginRenderPass to replace AttachRender
  • Switch RenderSoftwareCursors to use wlr_output_add_software_cursors_to_render_pass
  • Switch pkg-config package name for wlroots to wlroots-0.18
• Update tinywl to handle the initial commit for XDG surfaces, since wlroots no longer does this automatically
  • Updated tinywl to use toplevel/popup callbacks since it's now necessary
• Update Go dependencies
• Update Nix flake
  • Use buildGoModule
  • Avoid using with and rec as they are no longer best practice
  • Remove usage of gomod2nix as it is no longer needed
  • Update all dependencies
  • Apply formatting with nixfmt

There are a few minor things. The GeoBox API wrapper contained a pointer field that was only read and never written to, so it was removed, since the two usages of it were broken. Also, there are a lot of things that could be cleaned up or improved in the future. However, I was able to get this working and run applications in it, so hopefully pending any serious issues we can get this moving :)

[alexbakker]

Thanks!