fix(frontend): update ModelInfoResponse types to match backend structure

- Update TypeScript types to match flat backend response structure
- Remove nested model_info and metrics objects
- Remove label_config, use labels array and per_class_metrics array
- Update all component references to use new structure
- Generate default colors for prediction labels in CandleChart
- Fix TypeScript type errors for nullable model_version
- Remove accuracy/F1 metrics display (not in new response)

next-env.d.ts

@@ -1,6 +1,6 @@
 /// <reference types="next" />
 /// <reference types="next/image-types/global" />
-import "./.next/dev/types/routes.d.ts";
+import "./.next/types/routes.d.ts";
 
 // NOTE: This file should not be edited
 // see https://nextjs.org/docs/app/api-reference/config/typescript for more information.