Gvim under Linux: Quirky ligatures and no texture healing

Now that #17 is fixed (thank you!), I'm trying Monaspace out in Gvim again. The font appears, but texture healing isn't working, and when I try to enable ligatures, it's quirky.

Software versions:
- Linux Mint 21.3 Cinnamon
- Gvim 8.2.2121
- Monaspace v1.101

Gvim settings:
```
set guifont=Monaspace\ Neon
" The following line causes the quirky ligatures
set guiligatures=!\"#$%&()*+-./:<=>?@[]^_{\|~}
" Originally I had the following line as well, but since this setting only applies to Windows, it's irrelevant
set renderoptions=type:directx
```

The results look like [the example on the Monaspace website](https://monaspace.githubnext.com/#learn-more) with `Texture healing` unticked.

The attached screenshot is with `guiligatures` set; note that the slashes (`/`) at the beginning of the comments are offset to the left and not fully rendered. Interestingly, this doesn't happen when the block cursor is over it, so it might be an issue with Gvim or whatever it uses to render the character, but it would be helpful to know whether I'm setting this up correctly. Let me know if there are any other settings that I could try, or applications other than Gvim that you would expect to work. Thanks.