Verify YM C333 first-cumulant color cancellation

[stevemoraco]

Public theorem-equivalent verifier for RH-Lean C333 / #2272.

Verifies only the finite cancellation shadows used by the conditional source repair:

• odd contributions cancel under an equal-weight sign-symmetric two-point average;
• an antisymmetric color coefficient cancels against a symmetric covariance pair;
• an antisymmetric diagonal coefficient vanishes.

The guarded AXLE Lean 4.30 workflow rejects proof escape hatches, failed declarations, Lean/tool errors, and warnings.

It does not verify the Yang-Mills cubic vertex, Gaussian measure, structure constants, Faizal-Shabir P_irr, Banach RG, AF/IR identity, continuum OS reconstruction, a mass gap, or the Clay theorem.