Details:
- In case the table entirely fits into a single group size (`capacity <= Group::kWidth`), the order of elements is not important.
- For growing upto Group::kWidth we rotate control bytes and slots deterministically (using memcpy).
- We also avoid second find_first_non_full right after resize for small growing.
PiperOrigin-RevId: 588825966
Change-Id: I09bd7fd489e3868dcf56c36b436805d08dae7ab5
