Prove the producer-to-result contract with one three-event CI fixture

[proerror77]

Parent

#314

What to build

Add one small current-schema fixture with three independent BTC x 5m events and separate Up and Down books, then drive it through producer qualification, independent catalog admission, common-time cohort partition, snapshot materialization, pipeline_smoke, and the three typed research adapters. The fixture is the highest local/CI compatibility seam and must use public production contracts rather than test-only alternate parsers.

Acceptance criteria

• The fixture has one train event, one crossing event that must be excluded, and one held-out event, with independent Up and Down books and one causally projected Chainlink path per event.
• Producer qualification, independent ready catalog admission, and snapshot readback succeed through the same public contracts used in runtime.
• The common partition digest is identical for settlement, Up, and Down tasks.
• pipeline_smoke reaches Completed without MCTS and publishes a rehashable compatibility result.
• Bounded research_trial runs produce isolated settlement, Up, and Down receipts and one experiment manifest.
• Mutating held-out data cannot change train-only checkpoints or selected candidates but does change held-out result identity.
• Counterexamples fail for token swap, missing request outcome, corrupted trust anchor, crossing leakage, mutable snapshot identity, and shared checkpoint path.
• The fixture remains small enough for normal affected CI and does not require network, OSS, ACK, Docker build, or external services.

Blocked by

#318, #319, #320, #321, #322, #323, and #324

Out of scope

Cloud deployment, performance proof, production collector cutover, large historical datasets, and profitability claims.