fix: prevent asset conflicts between React and Grid.js versions

Add coexistence checks to all enqueue methods to prevent loading
both React and Grid.js assets simultaneously.

Changes:
- ReactAdmin.php: Only enqueue React assets when ?react=1
- Init.php: Skip Grid.js when React active on admin pages
- Form.php, Coupon.php, Access.php: Restore classic assets when ?react=0
- Customer.php, Product.php, License.php: Add coexistence checks

Now the toggle between Classic and React versions works correctly.

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

node_modules/eslint-plugin-import/index.d.ts

@@ -0,0 +1,33 @@
+import { ESLint, Linter, Rule } from 'eslint';
+
+declare const plugin: ESLint.Plugin & {
+  meta: {
+    name: string;
+    version: string;
+  };
+  configs: {
+    'recommended': Linter.LegacyConfig;
+    'errors': Linter.LegacyConfig;
+    'warnings': Linter.LegacyConfig;
+    'stage-0': Linter.LegacyConfig;
+    'react': Linter.LegacyConfig;
+    'react-native': Linter.LegacyConfig;
+    'electron': Linter.LegacyConfig;
+    'typescript': Linter.LegacyConfig;
+  };
+  flatConfigs: {
+    'recommended': Linter.FlatConfig;
+    'errors': Linter.FlatConfig;
+    'warnings': Linter.FlatConfig;
+    'stage-0': Linter.FlatConfig;
+    'react': Linter.FlatConfig;
+    'react-native': Linter.FlatConfig;
+    'electron': Linter.FlatConfig;
+    'typescript': Linter.FlatConfig;
+  };
+  rules: {
+    [key: string]: Rule.RuleModule;
+  };
+};
+
+export = plugin;