Add Phase 9 shared motion adapters

[snkmcb]

Summary

• add mmdSkeletonAdapter with the versioned MMD humanoid role table, shared skeleton descriptor, source rest pose, and target retarget map
• add mmdMotionAdapter to emit evaluated shared motion clips with root motion, morph and visibility channels, provenance, and boundary diagnostics
• wire digest-pinned motionCore and motionRetarget packages into CMake, OpenStrata manifests, boundary checks, and the installed-consumer lane
• update the motion contracts, capability matrix, diagnostics catalog, roadmap, README, and changelog
• preserve the VMD model name through motion binding for clip provenance

Review fixes

• preserve evaluated model visibility under mmd:model:visibility, separated from mmd:morph:<source name> to prevent channel collisions
• reject non-finite evaluated shared values with MMD_MOTION_NON_FINITE_SAMPLE instead of replacing invalid rotations with identity

Verification

• ost build
• ost test — 31/31 passed in Release, including boundary, documentation, integration, and installed-consumer tests
• ost plugin test --workspace --graph-only — valid: 1 bundle, 7 libraries, 13 library edges, 2 tools
• git diff --check