[Epic] Rework assets & static resources

[Josh Field]

• Introduce assets table as a replacement for scene service
• #9903
• Rework resources.json to be a partial, and only have deployment-independent info (hash, tags), and include asset entries
• Ensure file browser API is always used for CMS instead of static resources
• Move thumbnails field to asset table
• Asset table populated and updated for all GLTFs