Fix build issues caused by year-specific linter rule (#15780)

eslint.config.js

@@ -12,7 +12,7 @@ import prettierConfig from 'eslint-config-prettier';
 import importPlugin from 'eslint-plugin-import';
 import vitest from '@vitest/eslint-plugin';
 import globals from 'globals';
-import licenseHeader from 'eslint-plugin-license-header';
+import headers from 'eslint-plugin-headers';
 import path from 'node:path';
 import url from 'node:url';
 
@@ -210,19 +210,26 @@ export default tseslint.config(
   {
     files: ['./**/*.{tsx,ts,js}'],
     plugins: {
-      'license-header': licenseHeader,
+      headers,
       import: importPlugin,
     },
     rules: {
-      'license-header/header': [
+      'headers/header-format': [
         'error',
-        [
-          '/**',
-          ' * @license',
-          ' * Copyright 2025 Google LLC',
-          ' * SPDX-License-Identifier: Apache-2.0',
-          ' */',
-        ],
+        {
+          source: 'string',
+          content: [
+            '@license',
+            'Copyright (year) Google LLC',
+            'SPDX-License-Identifier: Apache-2.0',
+          ].join('\n'),
+          patterns: {
+            year: {
+              pattern: '202[5-6]',
+              defaultValue: '2026',
+            },
+          },
+        },
       ],
       'import/enforce-node-protocol-usage': ['error', 'always'],
     },