build: Update ESLint to v9 (#16639)

packages/@n8n/ai-workflow-builder/eslint.config.mjs

@@ -0,0 +1,11 @@
+import { defineConfig } from 'eslint/config';
+import { nodeConfig } from '@n8n/eslint-config/node';
+
+export default defineConfig(nodeConfig, {
+	rules: {
+		'unicorn/filename-case': ['error', { case: 'kebabCase' }],
+		complexity: 'error',
+		'@typescript-eslint/require-await': 'warn',
+		'@typescript-eslint/naming-convention': 'warn',
+	},
+});