feat(icons): disable mini.icons when not loaded

[yaowjit]

Description

use MiniIcons instead of require("mini.icons"), when not load mini.icons, there's no MiniIcons global variable

then, if not require("mini.icons").setup(), prefer to use nvim-wbe-devicons

Related Issue(s)

https://github.com/folke/snacks.nvim/issues/558

Screenshots

[github-actions[bot]]

This PR is stale because it has been open 30 days with no activity.

[folke]

no, since a lot of people lazy-load mini.icons