lib notify should implement vim.notify semantics and override it.

[ldelossa]

Currently litee.nvim uses its own notification mechanism which is pretty crude.

It can be found here: https://github.com/ldelossa/litee.nvim/blob/main/lua/litee/lib/notify/init.lua

It supports notifications which time themselves out along with persistent ones which will stick around until a subsequent API call is made.

Ideally, we refactor this lib to work with vim.notify api and semantics. This would allow for us to override vim.notify function optionally, and instead of all litee.nvim plugins calling into lib_notify, they will call "vim.notify" instead.

@zjp-CN does this sound something you'd be interested in doing?