feat(M14.5): add pointwise Mizera BCJ residue model

[jagg-ix]

Scope

Extends the merged M14 continuum AdS/double-copy lineage with the new Mizera theorem surface now present on entropic-physlib-linear-full.

• evaluates continuous pointwise three-channel BCJ numerator families;
• reconstructs all channels from the explicit four-puncture finite residues;
• verifies regularity at infinity as the same pointwise Jacobi closure;
• checks weighted generalized-gauge invisibility;
• checks a nontrivial nilpotent twisted differential and twisted-exact residue invariance;
• adds a standalone model registration, focused test, formal ledger, ZIL claim graph, and model note.

Formal authority

• jagg-ix/entropic-physlib-private
• branch entropic-physlib-linear-full
• tip 35f98f147771a4e250ec01b4cbf2afab72313db7
• BCJ source blob 96e5f7feb002125a633d90c3940e1af513bb8484

Toolchain

• Lean 4.31.0 / leanprover/lean4:v4.31.0
• jagg-ix/zil-lean@6daee2698304feb203c6adb91b2e8853613f85b5

Validation

pytest -q tests/test_m14_mizera_pointwise_bcj_m145.py
1 passed

The study closes all 8 acceptance groups.

Claim boundary

This is a conditional executable compatibility model. It does not claim a full CHY measure, the full Deligne--Mumford compactification, arbitrary loop-level numerator construction, or an unconditional global double-copy theorem.

Merge audit

• targets main directly;
• based on 93607ae7c147e071fe62d6f4c0a2d182f276477d;
• six new files only;
• no CI/workflow changes;
• no files shared with the companion M14.6 and M14.7 PRs.