[Cards & POS Services] Refactor routes and services

[sanducb]

Context

Created from this comment

Both card-service and point-of-sale services should have most of the logic in the corresponding service.ts, as otherwise, we are coupling the "application layer" with our actual domain code. If made this, say, a GraphQL API, we shouldn't need to change any of the domain logic about how we are handling events and making the payment work.

To do:

• Move payment event handling from routes to service layer (behavior must remain the same)

[salonisaboo]

Hello! I would like to work on this issue. Could you please assign it to me?

[ARYPROGRAMMER]

hey @mkurapov can i get this assigned, clearing this backlog asap