feat(proportion): torso snowman front waist pinch + chest flatten (0065)

[Ryan-AI-Studios]

Summary

• Front hourglass + flatter chest plate on oval torso RECIPE (0065-TorsoSnowmanFront)
• Waist rx hard max 0.80x post-taper chest when taper >= 0.10; female torso_waist_taper 0.14 -> 0.22
• Waist/chest ry fracs 0.58/0.85; full3d chest rear bias 0.28x ry (front_plane unbiassed)
• Pin retargets: 0047 magnitudes, 0053 T9, 0032 axial chest exception; dedicated T0-T13
• Product nofuse_0065: rx_w/rx_c=0.800, front=-0.0797, rear=0.1418; constraints green; D7 multi-view

Test plan

• uv run ruff check . / ruff format --check . / basedpyright / full pytest
• Dedicated tests/test_proportion_torso_snowman_front.py
• product_0056up re-emit work/.../nofuse_0065/ inventory + views face/left/3q
• Schema stay 1.4.0; MCP stay 46; no new C_*/CLI/PyPI

Honesty

RECIPE authoring only (N6 / Difficulty §12) — not mesh/print success.