options: add matchbracestyle (#2876)

* Update docs to include `matchbracestyle`

* Add `matchbracestyle` to infocomplete.go

* Add validator and default settings for `matchbracestyle`

* Highlight or underline braces based on `matchbracestyle`

* Add `match-brace` to default colorschemes

* Correct `FindMatchingBrace()` counting

Make brace under the cursor have priority over brace to the left in
ambiguous cases when matching braces

Co-authored-by: Dmitry Maluka <dmitrymaluka@gmail.com>

* Fix conflicts

---------

Co-authored-by: Jöran Karl <3951388+JoeKar@users.noreply.github.com>
Co-authored-by: Dmitry Maluka <dmitrymaluka@gmail.com>

internal/action/infocomplete.go

@@ -216,6 +216,13 @@ func OptionValueComplete(b *buffer.Buffer) ([]string, []string) {
 			if strings.HasPrefix("terminal", input) {
 				suggestions = append(suggestions, "terminal")
 			}
+		case "matchbracestyle":
+			if strings.HasPrefix("underline", input) {
+				suggestions = append(suggestions, "underline")
+			}
+			if strings.HasPrefix("highlight", input) {
+				suggestions = append(suggestions, "highlight")
+			}
 		}
 	}
 	sort.Strings(suggestions)