Prove quantum graph color restriction and N=6 consequences

[DomTheDeveloper]

Closed as superseded by #96.

PR #96 is a clean one-commit transplant built directly on current main. It preserves the complete 47-certificate proof, color-restriction theorem, four terminal consequences, status patch, and focused audit workflow without importing unrelated historical divergence.

The upstream integration stack remains tracked separately through #91 and infinityscroll#1.

[github-actions]

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