enhancement: allow max length for label, prevent label from covering up buffer content

[unphased]

The labels are often long and they actually cover up the buffer. Both of these features should be provided in order for show_label to be worth using. And if we dont show the label then all we can get are the counts which is not really enough to justify using.

Example

[luckasRanarison]

There's already the label_fmt option, you could do something like this:

{
  sings = {
    label_fmt = function(actions)
      local title = actions[1].title
      return #title < 20 and title or title:sub(1, 20) .. "..." -- truncating
    end
  }
}

[unphased]

Fantastic.