FINERACT-2790: Progressive loan MIR with ReAge allocation loop

[alberto-art3ch]

Description

A Merchant Issued Refund (MIR) with the LAST_INSTALLMENT future-installment allocation rule failed with an unmapped HTTP 500 on a progressive loan that had been re-aged (EQUAL_AMORTIZATION_PAYABLE_INTEREST) and then received an additional disbursement on an auto-down-payment product.

The symptom was not the NoSuchElementException fixed by 6347, but its sibling: an infinite allocation loop aborted by the LoopGuard (IllegalStateException: Loop exceeded 1400 iterations).

FINERACT-2790

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