test: add Next.js 16 params Promise handling regression tests

src/__tests__/unit/id-validation.test.ts

@@ -125,4 +125,36 @@ describe('ID Validation', () => {
       expect(isNaN(playerId)).toBe(true);
     });
   });
+
+  describe('Next.js 16 params handling', () => {
+    test('should handle params as Promise (Next.js 16 requirement)', async () => {
+      // In Next.js 16, params is a Promise
+      const params = Promise.resolve({ id: '123' });
+      
+      // This is how Next.js 16 expects params to be handled
+      const { id } = await params;
+      const parsedId = parseInt(id, 10);
+      
+      expect(parsedId).toBe(123);
+      expect(isNaN(parsedId)).toBe(false);
+    });
+
+    test('should handle invalid ID in Next.js 16 params', async () => {
+      const params = Promise.resolve({ id: 'invalid' });
+      
+      const { id } = await params;
+      const parsedId = parseInt(id, 10);
+      
+      expect(isNaN(parsedId)).toBe(true);
+    });
+
+    test('should handle empty ID in Next.js 16 params', async () => {
+      const params = Promise.resolve({ id: '' });
+      
+      const { id } = await params;
+      const parsedId = parseInt(id, 10);
+      
+      expect(isNaN(parsedId)).toBe(true);
+    });
+  });
 });