research(horizon): preserve 2026-09-19 H2 fail-closed state after later H1 delivery

[lostlight530]

Scope

Integrates the Jules-native 2026-09-19 H2 record exactly as a fail-closed execution, then adds a forward reconciliation after the same-day H1 later became visible on main.

Original execution

• Input Status: INPUT_MISSING
• Task Status: BLOCKED
• Network: NOT_RUN
• no orientation decision was fabricated
• no host/runtime/Actions change

Forward reconciliation

The later merged H1 path is now explicitly named, but the original H2 state is not replayed or upgraded.

LATER_PATH_PRESENT != ORIGINAL_TASK_INPUT_AVAILABLE

No retroactive SUCCESS, no reconstructed orientation, and no evidence upgrade were introduced.

Optimistic-lock integration

• Jules original commit remains in ancestry
• current main, including the later H1 delivery, was integrated as a second parent
• no rebase or force-push
• final compare before merge: behind 0
• merge is gated on exact expected head SHA 1fb5a268d6a89ecfd6f7eaf7eeca50d66e7e2563

Validation boundary

This delivery preserves task-time chronology and current-path truth as separate states. Merge success is not evidence that H1 was visible to the original H2 run.

[google-labs-jules]

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