FINERACT-2455: Working Capital Loan Charge-Off

[alberto-art3ch]

Description

Brings Charge-Off to the Working Capital Loan module

• New chargeOff / undoChargeOff transaction commands on /working-capital-loans/{id}/transactions, wired through the legacy command pipeline (audit trail + maker-checker).
• Charge-off marks the loan as charged-off and creates a non-monetary CHARGE_OFF transaction recording the outstanding balance. The tag is only removed by an explicit undo.
• Validations: single charge-off only, date not before the last transaction and not in the future, undo only when no monetary transaction follows the charge-off, and no new charges allowed after charge-off.
• Exposes chargedOff on the loan read model and a charge-off template (auto-calculated amount + date + reason options).

FINERACT-2455

Checklist

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