fix: code review cleanup - remove unused imports, replace any types with generics, fix test imports

apps/api/src/knowledge/services/cache.service.spec.ts

@@ -1,3 +1,4 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
 import { Test, TestingModule } from '@nestjs/testing';
 import { KnowledgeCacheService } from './cache.service';