Ensure `ComboboxInput` does not sync while you are still typing #3259

While you are typing, we should not sync the value with the `<input>` because otherwise it would override your changes. The moment you close the Combobox (by selecting an option, clicking outside, pressing escape or tabbing away) we can mark the component as not typing anymore. Once you are not typing anymore, then we can re-sync the input with the given value.