Evaluate current financial facts before recording event consumption

Context

Financial events can arrive more than once or after later changes to the receivable position.

Decision

Use event identity to select work, read current financial facts and retain the receipt only after processing succeeds.

Alternatives Considered

Use financial amounts from the delivered event. An event amount can be older than the financial position at evaluation time.

Store the event receipt before doing its work. An early success receipt would suppress recovery after failed processing.

Poll financial events through a retained cursor. The current implementation uses event invocation and position reads rather than cursor polling.

Consequences

Conditional opening prevents duplicate authorization, but earlier side effects can survive a failed event. The bounded sweep supplies partial recovery.