Update a PENDING financial transaction (dueDate, amount, paymentMethod, bankAccount and description). Structural fields (installmentNumber, periodicity, type, origin, status) are not changed. The optional 'scope' field controls propagation to the title's OTHER PENDING transactions: THIS_ONLY (default when omitted) edits only the target; ALL_PENDING also applies amount, paymentMethod, bankAccount and description to every other PENDING transaction of the same title (each one keeps its own dueDate); THIS_AND_FUTURE does the same but only for PENDING transactions whose dueDate is on or after the target's ORIGINAL dueDate (before the edit; ties included). Non-PENDING siblings are always ignored (not an error) and the target itself must be PENDING. The parent title's balance is recalculated once, as the sum of its PENDING transactions (new amounts included). The optional 'allocations' list (costCenterId, accountPlanSubAccountId, amount) has replace-all semantics: null leaves the transaction's allocations untouched; when present, the current allocations are deleted and recreated, and their sum must match the transaction's FINAL amount (0.01 tolerance). When the scope propagates the amount to siblings, the target's final allocations are propagated (replace-all) as well.