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/comment-parser/tests/e2e/issue-120.spec.js

@@ -0,0 +1,29 @@
+const {
+  parse,
+  stringify,
+  transforms: { align },
+} = require('../../lib/index.cjs');
+
+test('align - collapse postDelim', () => {
+  const source = `
+    /**
+     * Description may go
+     * over multiple lines followed by @tags
+     *        @param {string} name the name parameter
+     * @param {any} value the value parameter
+     */`.slice(1);
+
+  const expected = `
+    /**
+     * Description may go
+     * over multiple lines followed by @tags
+     * @param {string} name  the name parameter
+     * @param {any}    value the value parameter
+     */`.slice(1);
+
+  const parsed = parse(source);
+  const aligned = align()(parsed[0]);
+  const stringified = stringify(aligned);
+
+  expect(stringified).toEqual(expected);
+});