Add inner-keep 3D asset library

[ael-dev3]

What

• catalogs the complete 2026-08-02 inner-keep 3D production library
• adds a 13-image optimized gallery and a richer repository README
• records release checksums, source inventory, provenance, license boundaries, and privacy-sanitization audit
• keeps large Blend/GLB masters out of normal Git history in accordance with repository policy

Library

• 152 distinct assets
• 610 GLBs total (604 production runtime LOD files plus 6 inspection catalogues)
• 74 Blender containers
• 364 PNGs

Verification

• python3 -m unittest discover -s tests -v — 32 passed
• python3 scripts/verify_release.py --manifest releases/inner-keep-3d-asset-library-2026-08-02/manifest.json --asset-dir <artifact-dir> — passed
• all package checksum entries, JSON, PNG, GLB, and Blender headers validated
• private authoring paths and macOS metadata removed from the public copy
• runtime GLBs remain byte-identical; sanitized PNG pixels remain identical

The corresponding GitHub Release attachment is published separately because the verified library archive is about 224 MiB.