test: update unit test for nodeName field in validation response

Update expected validation response to include nodeName field in warnings.

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

tests/unit/mcp/handlers-n8n-manager.test.ts

@@ -980,6 +980,7 @@ describe('handlers-n8n-manager', () => {
           warnings: [
             {
               node: 'node1',
+              nodeName: 'node1',
               message: 'Consider using newer version',
               details: { currentVersion: 1, latestVersion: 2 },
             },