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/framer-motion/dist/es/utils/reduced-motion/index.mjs

@@ -0,0 +1,19 @@
+import { isBrowser } from '../is-browser.mjs';
+import { hasReducedMotionListener, prefersReducedMotion } from './state.mjs';
+
+function initPrefersReducedMotion() {
+    hasReducedMotionListener.current = true;
+    if (!isBrowser)
+        return;
+    if (window.matchMedia) {
+        const motionMediaQuery = window.matchMedia("(prefers-reduced-motion)");
+        const setReducedMotionPreferences = () => (prefersReducedMotion.current = motionMediaQuery.matches);
+        motionMediaQuery.addListener(setReducedMotionPreferences);
+        setReducedMotionPreferences();
+    }
+    else {
+        prefersReducedMotion.current = false;
+    }
+}
+
+export { initPrefersReducedMotion };