Preserve submission credit when baseline admission is closed

[camfairchild]

A finalized submission arriving after its commissioned baseline closed received baseline_closed_at_submission as a candidate FAIL, leaving its evaluation credit consumed. Reject it before screening as expired / NO_DECISION and release its credit or cited payment in the same transaction, so the miner can resubmit against an open baseline.

The dashboard submission details and miner report now explain: “This baseline closed before your submission. Your submission credit has been preserved.” They direct the miner to the current open baseline. Historical FAIL rows are not presented as having received a credit refund.

Consumer: prepare_screen_queue in routed coordinator and synchronous-validator admission, plus dashboard details and miner reports. Casualty: the late-baseline mark_failed call. Extract the existing closed-target credit/payment release transaction for reuse; keep the existing error code and cutoff boundaries. No historical data rewrite, new schema, GPU behavior change, or deployment.

Validation:

• 220 tests passed across intake, parallel arenas, closed targets, miner feedback, dashboard metrics, coordinator, validator loop, duplicate replay, settlement and baseline segments. The final strengthened credit assertions and report guard were followed by 53 passing focused tests.
• Coverage verifies credit and payment reuse after restart, two competition/target profiles, same-block eligibility, idempotent retirement, unchanged early submissions, resubmission of identical bytes against a new commission, and no refund notice on historical FAIL rows.
• Ruff, dashboard JavaScript syntax, documentation links, strict MkDocs build, module reachability, assertion/line ratchets, all 10 identity snapshots, and diff whitespace checks passed.

Documentation: updated miner diagnostics with the no-charge rejection and exact message. Directory line ceilings reflect this change; the oversized intake file shrinks by 21 lines. Production +40/-29 (net +11), docs +5/-1, tests +45/-9, ratchet accounting +5/-5; total +95/-44 (net +51).