feat(router): add total count for payments list (#1912)
Files to modify:


**payments.rs**
  Add:
    - struct: pub::PaymentListResponseV2

**payment_intent.rs**
  Modify existing code

**payment_attempt.rs**
  Modify existing code

**payment_attempt.rs**
  Modify existing code

**payments.rs**
  Add:
    - struct: pub::PaymentListResponseV2

**helpers.rs**
  Add:
    - function: pub::validate_payment_list_request_for_joins

**payment_attempt.rs**
  Modify existing code

**payment_intent.rs**
  Modify existing code

**payments.rs**
  Add:
    - struct: pub::PaymentListResponseV2

**payment_intent.rs**
  Modify existing code