Audit latest-main A100434 upstream candidate

[DomTheDeveloper]

Replays the exact one-file A100434 Google-facing candidate on current upstream main at f776d2f2039351b00737ffcafb9d7d7666e1d9af.

Audit-only. Do not merge. Promote to _PRs/ready/ only if copyright and full Lean build are green.

[github-actions]

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