purifyForReceipt abstract method
Purifies message data for use in ReceiptCommand.
Extracts and cleans up metadata from the original message envelope/content to form the "origin" field in receipt commands (removes sensitive/redundant fields). Returns null if the envelope is null (invalid original message).
@param envelope - Optional envelope of the original message for receipt
@param content - Optional content of the original message for receipt
@return Normalized map containing core receipt origin metadata (null if envelope is null)
Implementation
Map? purifyForReceipt(Envelope? envelope, Content? content);