Polish shop previews, stamp/cursor assets, and character icon motion

[kiyarose]

Summary

• fix character rendering regressions caused by SVG toggle/layer handling so body/hair assets stay visible and hair toggles do not leak detached fragments
• stabilize arm animation transforms by preserving per-node base transforms, resetting before each pose transition, and applying pose rotations against fixed pivots
• recalibrate pose angles so idle/present/think/write/shop/wave are visibly distinct in Character Lab and side mascot contexts
• keep the Character nav badge centered by rendering from a cropped headshot data URL with the active appearance
• make side mascot placement sticky in a dedicated right column across desk layouts on large screens
• slim cursor rendering by moving cursor asset generation into shopCursorAsset.ts and reducing render size/hotspots for preview + live cursor CSS

Walkthrough artifacts

character_assets_pose_sidebar_cursor_demo.mp4
Character Lab assets visible
Wave pose distinct
Single sticky settings character
Slim shop cursor preview

Validation

• npx eslint src/features/shop/shopCursorAsset.ts src/features/shop/shopCosmetics.tsx src/features/shop/Shoppe.tsx src/features/character/CharacterNavIcon.tsx src/features/character/DeskCharacterLayout.tsx src/features/character/MentellCharacter.tsx src/features/character/applyCharacterAppearance.ts src/features/character/characterPoses.ts src/features/character/useArmPoseAnimation.ts
• npm run build:check
• manual browser QA on http://127.0.0.1:4173/ covering Character Lab assets/hair/poses/sleeves, centered nav badge, settings sticky side mascot, and slim shop cursor preview

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