Current funded performance work after #1914 journal changes

[zileria354-ship-it]

Before posting a funding proposal around #1914, I checked the release branches and found that #1930 and #1932 already implement the mutation-journal work that would have formed its central scope. I will not claim or propose compensation for that existing implementation.

There is a narrower TurnTracker.Clone / heartbeatAt copying path in the reviewed v5/v6 branches, but v4.2 lacks it, and on-chain governance proposal 114 was described as approving v4.2 and removing v5. A benchmark of main's earlier path would not justify work on the replacement release.

Is there an unclaimed, current-release performance task that the maintainers want addressed under an explicitly agreed USDT milestone budget? I had prepared a 15,000-USDT engineering scope, but am holding it until the target, overlap, acceptance tests, governance sponsor, payment asset/network and funding process are confirmed. The amount is a proposed negotiation budget, not a demand or an existing reward.

I can provide a reproducible baseline, a reviewed implementation, differential correctness checks and before/after measurements once those conditions are agreed. Please identify any existing owner or funded assignment first. No live-network changes, expenses, or contract acceptance are proposed by this message.