Fix up CreateTextureViewError::TooMany{MipLevels,ArrayLayers} crashes and style

[ErichDonGubler]

Connections

Regressed by #8323, which I reviewed. 😅

Description

These error variants use a naive base + offset from user-provided input in order to be diagnostically helpful in Display. Eek! Add a BasePlusOffset structure that can be safely used to show calculations like this, falling back to displaying <overflow> if it doesn't work, and use that instead of the naive addition.

Also, fix up some styling stuff that I noticed was wrong and/or not consistent with other parts of code. See individual commits for more details.

Testing

TBD. I'd like to see a CTS test for this, since this is prime validation coverage that doesn't appear to be tested.

Squash or Rebase?

rebase plz

Checklist

• If this contains user-facing changes, add a CHANGELOG.md entry.

[ErichDonGubler]

This is basically ready for review, but I haven't yet determined how I'd like to test this.