Weapon grip anchor: gizmo-authored WYSIWYG grip + operator's hand-tuned grip baked

WeaponGripAnchor under Hand_R in Player.prefab carries the actual axe
mesh as an EditorOnly preview (baker skips it; play-verified single axe)
so grip manipulation is the real model live in the prefab stage;
AttachMeleeWeapon reads the anchor (consts = seed/fallback). Includes
the operator's first gizmo-tuned grip (rebaked mesh matches expected
radius exactly). PlayerRigTools also carries the heavy-lock clip
re-speeds (1.0/0.85/0.88) consumed by the next commit.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Assets/_Project/Materials/M_Weapon_Preview.mat.meta

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