Force tty mode | Diff and LSP gutter symbols in tty

[glm729]

Originally, I saw this: #6206
This would possibly be handy for me, but my angle might be able to be solved through other means.

I'm working with a set of mixed-capability machines (but not via SSH), some tty-only and some with xterm but bitmap fonts only, as well as machines with more complete terminal emulators e.g. WezTerm. In short, config would be useful, but I am also wondering if there's a way to force tty-mode.

This is mainly due to the absence of rendered characters for diff and LSP symbols in the gutter -- is this able to be switched based on whether Helix is being run in e.g. tty2, or do the diff and LSP symbols in the gutter typically not render in a tty?