UTFANSWF v21 — Row 20 Thin-Slice Attribution Diagnostic

Run from the project root:

  python tools/row20_thin_slice_attribution.py

Outputs:

  results/row20_h0_attribution/REPORT.md
  results/row20_h0_attribution/row20_thin_slice_attribution.json

Rules preserved:

  - no physics changes
  - no threshold changes
  - no dataset changes
  - no new parameters
  - no gate verdict changes

Purpose:

  This diagnostic makes the existing Row 20 residual structure native and reproducible.
  It identifies which thin-slice nodes dominate the CMB/BAO/SN stress before any v21.1
  candidate can be considered.
