Add anchor time setting to Admin > Caching (#22839)

* Update `SegmentedControl` variant style getters

* Add `fill-all` variant to `SegmentedControl`

* Fix `SegmentedControl` borders

* Make `TimeInput's` clear button optional

* Extract `useTimeInput` hook

* Add `CompactTimeInput`

* Add anchor time setting

* Only show anchor time if refresh interval >= 6 hours

* Show refresh time hints under the anchor input