[cmccomb]

Summary

• Reclassify the two RM3 PTO Extension free decays as unchanged published-input independent_motion after the portable physical gate in Gate unchanged RM3 PTO Extension inputs with physical Python runs #664.
• Update the disjoint ledger to 52 independent motion, 5 corrected-only motion, 2 stationary force, and 4 qualified cases. The accepted total stays 59/63 and RM3 stays 21/21; nine original inputs remain without a qualifying unchanged-input gate.
• Preserve the corrected fine-step fixture history and explain the narrow inherited-limit passes and the published MATLAB source-step sensitivity. This does not claim pointwise reproduction or source convergence.

Evidence and checks

• The exact-head Gate unchanged RM3 PTO Extension inputs with physical Python runs #664 pinned MATLAB regeneration and physical gate passed.
• python3 tools/render_parity_badge.py --check
• python -m pytest -q tests/test_parity_ledger_csv.py (3 passed)
• git diff --check

Stack and merge condition

This is a draft stacked on #664 (codex/rm3-pto-original-physical) and contains only ledger commits above that branch. Merge only after #664 full Python CI is green and #664 has merged. Then retarget this PR to master, verify its exact-head checks, and review the final diff. The #624 issue text will be handled separately after the ledger merge.