feat(face-motion): finalize resume portrait interpolation - #66

What changed

• Replaced resume header portrait with multi-directional, pointer-driven face motion using a final GPT Image 2 generated v12 asset set.
• Added deterministic asset manifest and provenance docs for the 9-direction face rig and transition frames.
• Added scripts for face-motion generation verification, transition validation, and QA.
• Updated resume page components to bind full-page pointer movement and smooth sector interpolation logic.
• Updated Next config for cache-safe image delivery of generated pose assets.

Why

The user requested smoother, stable pose transitions while preserving exact likeness and pose consistency across the full portrait motion set.

Validation

• Manual verification: 9 direction sources mapped and browser-checked, with consistency checks passing.
• Added tests/face-motion.test.mjs to enforce deterministic pose mapping and transition expectations.
• Updated runtime flow used in header portrait path.