Add "format" to the "imageUrlHash" field in the OpenAPI spec because it is a 64 bit integer

[magiccrafter]

Problem
The imageUrlHash field in our API’s OpenAPI spec is a 64-bit integer, but it’s missing a format attribute. Without it, the spec doesn’t clearly explain how the field should be understood or used. Adding a format gives more detail beyond just “it’s a number,” which helps people and client generators better work with the API.

Proposed Fix
Add format: int64 to the imageUrlHash field. This tells everyone (and everything) that it’s a 64-bit integer.