fix(0131-FaceNoseTipCenterOffset): measured nose_tip Y as tip; compare vs front surface

[Ryan-AI-Studios]

Summary

• Measured finite nose_tip y_m now writes ellipsoid center = tip + nose_ry (Loomis parity) so the front surface seats on the captured tip.
• blockout-face-compare Y for nose_tip compares against front surface center[1] - ry_m when ry_m is finite; missing/non-finite ry_m falls back to center (no NaN).
• _delta_mm(..., role_id) — production call passes lid (B17). JSON recipe.center stays the ellipsoid center (no schema bump).

Honesty (N6)

FACE_COMPARE_HONESTY / RECIPE_HONESTY — authoring QA only; green compare ≠ print success. No remake/D7 (Loomis path unchanged; Default Package A still lacks measured nose Y).

Test plan

• T1 measured Y → center = y_m + ry_m; ry_m == NOSE_RY_FRAC_H * H
• T2 Loomis test_face__nose_tip_y_freeze
• T3 surface match → |delta.y| < 1 mm / hold_priors
• T4 0102 + nose fracs; T5 eye Y as center; T6 MCP 53; T7 missing ry fallback
• Four gates: ruff / format --check / basedpyright / pytest
• Codex R1: implementation PASS (review.md at ship)

Out of scope

0137 num_faces max; 0132–0136 leftovers; MCP 54; remake.

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Note

Low Risk
Authoring-only face recipe/compare geometry; no schema, auth, or print-path changes. Wrong Y offset would only skew QA deltas and nose placement.

Overview
Treats measured nose_tip Y as the tip, not the ellipsoid center, so the nose soft mass seats with its front surface on the captured landmark.

When y_m is finite, RECIPE_nose_soft center is now tip + nose_ry (same offset as the Loomis fallback). Face-compare Y for nose_tip uses center[1] - ry_m when ry_m is finite; missing/NaN ry_m falls back to center with no NaN. JSON recipe.center is unchanged (still the ellipsoid center).

Scale constants (NOSE_RY_FRAC_H, NOSE_TIP_Y_FRAC_RY) stay frozen. Authoring QA only.

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