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/rxjs/dist/esm/internal/scheduled/scheduleAsyncIterable.js

@@ -0,0 +1,23 @@
+import { Observable } from '../Observable';
+import { executeSchedule } from '../util/executeSchedule';
+export function scheduleAsyncIterable(input, scheduler) {
+    if (!input) {
+        throw new Error('Iterable cannot be null');
+    }
+    return new Observable((subscriber) => {
+        executeSchedule(subscriber, scheduler, () => {
+            const iterator = input[Symbol.asyncIterator]();
+            executeSchedule(subscriber, scheduler, () => {
+                iterator.next().then((result) => {
+                    if (result.done) {
+                        subscriber.complete();
+                    }
+                    else {
+                        subscriber.next(result.value);
+                    }
+                });
+            }, 0, true);
+        });
+    });
+}
+//# sourceMappingURL=scheduleAsyncIterable.js.map