* Add unit tests for large digit count in unique names
* Updated to use arbitrary-precision unsigneds
Passes the new unit tests, all diagnostics, and resolves Issue 19881
* Place UnlimitedUnsigned at top level and add unit tests
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
---------
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
