fix: resolve TypeScript errors in test files

- Fixed MCP_MODE type assignment in console-manager.test.ts
- Fixed prototype pollution test TypeScript errors in fixed-collection-validator.test.ts
- All linting checks now pass

🤖 Generated with [Claude Code](https://claude.ai/code)

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

tests/unit/utils/console-manager.test.ts

@@ -16,7 +16,7 @@ describe('ConsoleManager', () => {
     // Clean up after each test
     manager.restore();
     if (originalEnv !== undefined) {
-      process.env.MCP_MODE = originalEnv;
+      process.env.MCP_MODE = originalEnv as "test" | "http" | "stdio" | undefined;
     } else {
       delete process.env.MCP_MODE;
     }
@@ -250,7 +250,7 @@ describe('ConsoleManager', () => {
     });
 
     test('should handle empty MCP_MODE', () => {
-      process.env.MCP_MODE = '';
+      process.env.MCP_MODE = '' as any;
       
       const originalLog = console.log;
       

tests/unit/utils/fixed-collection-validator.test.ts

@@ -529,14 +529,14 @@ describe('FixedCollectionValidator', () => {
       };
       
       // Add prototype property (should be ignored by hasOwnProperty check)
-      Object.prototype.maliciousProperty = 'evil';
+      (Object.prototype as any).maliciousProperty = 'evil';
       
       try {
         const result = FixedCollectionValidator.validate('switch', config);
         expect(result.isValid).toBe(false);
         expect(result.errors).toHaveLength(2);
       } finally {
-        delete Object.prototype.maliciousProperty;
+        delete (Object.prototype as any).maliciousProperty;
       }
     });