Add result-final event

- Fires like result, but only after the input stream closes
- Use for one-shot per-query actions that would otherwise re-fire on
  every intermediate snapshot during loading

Close #4835

src/options.go

@@ -1063,6 +1063,8 @@ func parseKeyChords(str string, message string) (map[tui.Event]string, []tui.Eve
 			add(tui.Focus)
 		case "result":
 			add(tui.Result)
+		case "result-final":
+			add(tui.ResultFinal)
 		case "resize":
 			add(tui.Resize)
 		case "one":