FINERACT-2455: Fix COB amortizing discount fee before payment, fix WC loan closedOnDate wrong when backdated transaction closes

[Cocoa-Puffs]

Description

Describe the changes made and why they were made. (Ignore if these details are present on the associated Apache Fineract JIRA ticket.)

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[adamsaghy]

Please review the below findings / concerns:

the undoTransaction call site is a no-op in the case it was added for

WorkingCapitalLoanTransactionProcessor.recalculateClosedOnDate's javadoc says it "must be called wherever determineAndTransition can stamp a closure … the repayment path here, a discount fee adjustment, and a transaction undo", and the PR duly adds it at WorkingCapitalLoanWritePlatformServiceImpl.java line 1145. That call can never fire there:

• undoTransaction transitions with DateUtils.getBusinessLocalDate(), so any closure it stamps carries today's date.

• Future-dated transactions are rejected (WorkingCapitalLoanDataValidator), so MAX(repayment date) <= today, and the isBefore guard is always false.

The reachable case it would need to fix is the mirror image: validateUndoTransaction explicitly allows OVERPAID, so undoing an overpaying repayment that leaves the loan exactly settled fires LOAN_REPAID_IN_FULL and stamps closedOnDate = the undo day, while maturedOnDate keeps the earlier date it got when the loan first went overpaid. You end up with timeline.closedOnDate after timeline.actualMaturityDate — the drift the settlementDate javadoc says these two should not have. Pre-existing, not a regression, but the javadoc currently overstates what the call does.

Smaller, same shape: recalculateClosedOnDate returns early unless isClosedObligationsMet(), so on the overpaid path maturedOnDate is never corrected. A backdated repayment tipping a part-paid loan into OVERPAID leaves actualMaturityDate at the backdated date even though recalculateOverpaidOnDate fixes overpaidOnDate and settlementDate uses the corrected value for the amortization.