Update safeParseJson to check for dangerous object keys recursively

Improve detection of prototype pollution patterns in JSON parsing

tests/utils.test.ts

@@ -138,11 +138,22 @@ describe('Validation Functions', () => {
       expect(() => safeParseJson('{invalid json}')).toThrow('Invalid JSON');
     });
 
-    it('should throw on code injection patterns', () => {
+    it('should throw on dangerous object keys', () => {
       expect(() => safeParseJson('{"constructor": "function(){}"}')).toThrow('dangerous');
       expect(() => safeParseJson('{"prototype": "something"}')).toThrow('dangerous');
       expect(() => safeParseJson('{"__proto__": "something"}')).toThrow('dangerous');
-      expect(() => safeParseJson('{"function": "alert"}')).toThrow('dangerous');
+    });
+
+    it('should allow legitimate content containing function-related words', () => {
+      // Should not throw - these are legitimate values, not dangerous keys
+      expect(() =>
+        safeParseJson('{"message": "The function constructor is used to create objects"}')
+      ).not.toThrow();
+      expect(() =>
+        safeParseJson('{"content": "JavaScript prototype inheritance is powerful"}')
+      ).not.toThrow();
+      expect(() => safeParseJson('{"code": "function example() { return true; }"}')).not.toThrow();
+      expect(() => safeParseJson('{"function": "alert"}')).not.toThrow(); // function as key is now allowed
     });
 
     it('should throw on deeply nested JSON', () => {