refactor(P11+P12): codebase hygiene — CLAUDE.md rewrite, type safety, dead code removal

- Rewrite CLAUDE.md to match current 8-service architecture (was 11, 5 deleted)
- Remove all as-any casts in OrderDetail.tsx (9 casts → 0)
- Add cad_parsed_objects/cad_part_materials to OrderItem interface
- Rename require_admin → require_global_admin across 6 router files (22 calls)
- Remove EXPORT_GLB_PRODUCTION enum + generate_gltf_production_task (dead code)
- Remove worker-thumbnail from ALLOWED_SERVICES, replace Flamenco link
- Delete obsolete PLAN.md (1455 lines) and PLAN_REFACTOR.md (1174 lines)
- Fix digit-only USD prim names with p_ prefix

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/api/cad.ts

@@ -92,12 +92,6 @@ export async function generateGltfGeometry(cadFileId: string): Promise<GenerateG
   return res.data
 }
 
-/** Queue production GLB export (Blender + PBR materials) from geometry GLB. */
-export async function generateGltfProduction(cadFileId: string): Promise<GenerateGltfResponse> {
-  const res = await api.post<GenerateGltfResponse>(`/cad/${cadFileId}/generate-gltf-production`)
-  return res.data
-}
-
 export interface ParsedObjectsResponse {
   cad_file_id: string
   original_name: string