feature: index letter should be putted 1 or 2 letters after the corrent search string.

[meicale]

Did you check the docs?

• [X] I have read all the flash.nvim docs

Is your feature request related to a problem? Please describe.

NOW, the index letter is just after the search string. If someone to want to search more to get fewer chooses, it is not easy to figure out what to type next.

Describe the solution you'd like

Put the index letter 1 or 2 letter after the search string.

Describe alternatives you've considered

Pride a option for the user to decide how many letter should be.

Additional context

No response

[folke]

Set opts.label.after = {0, 2}