moment.js invalidAt() support?

Hi,

Do you have plans to implement moment's invalidAt() in dayjs? Can I maybe get this kind of information from dayjs any other way?

Quote from https://momentjscom.readthedocs.io/en/latest/moment/01-parsing/15-is-valid/

> Additionally, you can use moment#invalidAt to determine which date unit overflowed.
>
> var m = moment("2011-10-10T10:20:90");
> m.isValid(); // false
> m.invalidAt(); // 5 for seconds
>
> The return value has the following meaning:
>
> years
> months
> days
> hours
> minutes
> seconds
> millisecond

Read the issue's Moment.js invalidAt() example alongside Day.js's isValid() behavior, then determine the intended public API and overflow-unit semantics. Done means the scope is settled for reporting the invalid unit or documenting an alternative, with behavior validated for the quoted seconds-overflow case.

Written by the indexing model from the issue text.