fix(menu): Don't apply selected_text style to matched text in suggestions

[ysthakur]

#798 broke completion menu highlighting, which included making it so that the selected_text style was applied to matched text. #991 tried fixing #798 but missed the matched text problem. This PR makes it so that matched text only has the text and match/selected_match styles applied to it.

This is just a temporary fix. This works for now because suggestion values can't contain ANSI escapes, but once we start allowing suggestions to provide a separate display value with ANSI escapes, we need to handle the Reset attribute (0). It would also be good to handle consecutive ANSI escapes, but that one's not necessary.

Testing

Here's what Nushell looks like after this PR:

Nushell config:

  {
    name: completion_menu
    only_buffer_difference: false
    marker: $" \n❯ (char -u '1f4ce') "
    type: {
      layout: columnar
      columns: 4
      col_width: 20   # Optional value. If missing all the screen width is used to calculate column width
      col_padding: 2
      tab_traversal: "vertical"   # Direction in which pressing <Tab> will cycle through options, "horizontal" or "vertical"
    }
    style: {
      text: { fg: "#33ff00" }
      selected_text: {attr: r}
      description_text: yellow
      match_text: {attr: u}
      selected_match_text: {fg: darkorange attr: b}
    }
  }

[fdncred]

cool. looks better! thanks!