Release escrowed funds to the worker after task approval.
The on-chain flow: Escrow contract -> PaymentOperator.release() -> Worker USDC
This is an irreversible operation. Once released, funds go directly
to the worker's wallet. For dispute resolution after release,
use em_escrow_dispute.
Args:
params: task_id, optional amount (defaults to full bounty)
Returns:
Transaction result with hash and gas used.
Connector