Audit the explicit nine-point Erdős 100 construction

[DomTheDeveloper]

Green result

The complete explicit Piepmeyer witness proof now replays successfully against the current catalog definitions and pinned Lean toolchain.

It verifies a concrete A : Finset ℝ² with:

• A.card = 9;
• DistancesSeparated A;
• diam (A : Set ℝ²) < 5.

Immutable provenance

Historical source blob:

db773dd78975db6da5aed05c05c6eff1a26112b5

Audit branch head:

ac6d0f804114149b70673549d2d8494eeab9195c

Focused run 30213263093 passed:

• exact source-blob verification;
• current catalog-module build;
• proof-only source generation;
• no-hole/no-trust scan;
• complete Lean compilation;
• exact theorem axiom audit.

Axiom footprint:

[propext, Classical.choice, Quot.sound]

No sorryAx or compiler-trust dependency appears.

Status

Green proof recovery. The canonical admitted declaration still needs a focused restoration patch before promotion to _PRs/ready/. This audit-only PR should not merge.

[github-actions]

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