Optional cursorword highlighting in insert mode

[noelevans]

Cursorword highlighting may not be desired when in insert mode. When cursorword highlighting uses fg and bg options particularly, the highlighting of the current word feels distracting. For example if the user is typing the word "return", highlighting triggers for "ret", "retu", "retur" and finally "return". Attaching example screenshot to ticket.

[noelevans]

Here is cursorword highlighting while typing a return statement (in the main code) which for my use feels a bit distracting:

It then works as desired once the word is completed and normal mode is active:

The above screenshots are using these settings

require("nvim-cursorline").setup({
  cursorline = {
    enable = false,
  },
  cursorword = {
    enable = true,
    min_length = 1,
    hl = {
      fg = "#c0caf5",
      bg = "#565f89",
      underline = false,
    },
  },
})

[noelevans]

Hi @yamatsum so I'm proposing this change which would make highlighting of the current word in insert mode as optional, defaulting to the current behavior (actively highlighting). I would like to be able to turn off insert mode highlighting. I wondered if you'd accept this PR to make that possible. Many thanks, Noel