Raise an owned live bounty amount

Raises an open or in-progress posted bounty. The amount must increase; pot and repair bounties use pledges instead. A live prefunded x402 payment prevents the change. A card checkout from posting that is not paid yet is closed first, and the new amount is paid with a new checkout. A bounty already paid for answers 409; add to it with a pledge. The dashboard raise form is available only before payment.