- GridifyParams wrapper: nullable page/pageSize/filter/orderBy so list endpoints
work with no query params (Gridify's non-nullable int Page made [AsParameters]
treat them as required -> 400). Defaults page=1,pageSize=20.
- Normalize incoming filter '==' -> '=' : the frontend gridify.ts emits '==' for
equals (its convention) but Gridify's equals is '='. Safe (values are escaped;
!= >= <= =* contain no '=='). Fixes status==Active (frontend default that 500'd).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>