fix: asegurar re-proyeccion de UVMap y preservacion de materiales PBR originales si falla el horneado en Blender

fix: proteger ejecucion de QuadriFlow en modo headless de Blender para evitar cierres de sesion

Include tris_convert_to_quads in fast cleanup pipeline to prevent CYCLES baking memory spike

Use non-destructive fast cleanup for FBX export to preserve original UV mapping, materials, and textures without distortion

Fix EXT_texture_webp GLB import error in Blender by upgrading to Blender 4.2 LTS and sanitizing glTF extension headers

Restructure repository layout: move server and scripts to backend/ and web assets to frontend/ (ignore database and generated outputs)