NitroImg v1.2.1 - Resized-Crop Detection

A maintenance fix for the missing-size backfill added in 1.2.0.

Fixes

• Catches resized crops, not just new sizes - when an image size is re-registered at new pixel dimensions but keeps its name, the backfill now detects that its WebP is out of date and regenerates it. Before, only entirely new size names were noticed, so a changed crop kept pointing at the old WebP.