Support for separate `city` and `locality` / sub-locality in address model

[maxl2287]

Problem description
Currently the KYC-Match and KYC-Fill-in APIs only provide a single locality field in the address structure.
However, many address data providers (e.g. in Germany) distinguish between two different concepts:

locality → often represents the smaller locality / district
city → represents the official municipality / city

This distinction is common in several countries and leads to mapping challenges when integrating external address sources with the CAMARA KYC APIs. As a result, integrators are forced to make arbitrary decisions about which value to use for the locality field, which can negatively impact match quality and success rates.

Possible evolution
Introduce an optional city field (or alternatively subLocality / district) in the address schema used by KYC-Match and KYC-Fill-in.
This would allow:

Clearer mapping from external address providers
Higher match accuracy by sending the most appropriate value(s)
Better support for countries with multi-level locality structures

[PedroDiez]

Hi @maxl2287,

Just to clarify, in Germany are there addresses were both locality and city are required?
Would be possible to have an example, I think it would help in the understanding