Agreed. We've almost eradicated our usage of JS Date - fixing plenty of bugs along the way, and then I extracted thousands of lines of conversions and formatting from our production app (scheduling focused) into a temporal-fun package to make it Temporal more ergonomic for lots of common cases.
npmjs.com/package/temporal-fun
That looks neat although your package is missing a link to the source repository.
In fact, depending on the model, the battery replacement may well have also entailed replacing the whole top cover (including the keyboard).