[shadow-validation] stripe/repeat_payment response charges typeDiff (cloud#16965)

[AmitsinghTanwar007]

Shadow-validation diff: stripe/repeat_payment charges response field

Tracks HS↔UCS shadow-validation diff
router.typeDiff:response.Ok.TransactionResponse.charges {hs: object, ucs: null}
for connector stripe, flow repeat_payment, merchant yucca
(juspay/hyperswitch-cloud#16965).

For a split recurring payment, HS-native builds a charges response object from the
connector's split charge details, but on the UCS shadow path it came back null because
the recurring-charge response proto had no slot for split charges.

Fix: UCS adds splits to RecurringPaymentServiceChargeResponse and maps it
(juspay/hyperswitch-prism#1620); HS reads response.splits → charges on the repeat path.