Permissions required: Reject Operations

Reject an in-progress transaction. The caller's API key must hold the
Reject Operations permission for the source vault. Operations already
in a final state return 409 Conflict.

Only withdrawals, transfers, delegations, and generic operations
(including bridge transactions) can be rejected via this endpoint;
rejecting any other operation type returns 409 Conflict.

A transaction can only be rejected before it has been submitted for
signing and broadcast to the network. This endpoint cannot be used to
cancel a transaction stuck in the broadcasting state due to a low gas
fee.