[Performance] cache ContactDetails

[osmaczko]

Description

getContactDetails is called a lot. Every time it is called, it calculates color hash, which results in high cpu usage.

Acceptance criteria

• Cache ContactDetails instead of ContactsDto (https://github.com/status-im/status-desktop/blob/1e5fee981e5ae534c9f8f24cb44254becd738395/src/app_service/service/contacts/service.nim#L93)