Create strict requirement for ISO date format in the openapi spec

[Agash]

Got confirmation that the date filters accept the format as

%Y-%m-%dT%H:%M:%S.000Z

Ex 2026-01-14T23:59:03.000Z

https://api.goaffpro.com/v1/user/feed/orders?site_ids=165328,132230&limit=5&offset=0&created_at_max=2026-01-15T00:04:03.000Z&created_at_min=2026-01-14T23:54:03.000Z

Originally posted by @WolfwithSword in #1