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/lodash/_baseRandom.js

@@ -0,0 +1,18 @@
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeFloor = Math.floor,
+    nativeRandom = Math.random;
+
+/**
+ * The base implementation of `_.random` without support for returning
+ * floating-point numbers.
+ *
+ * @private
+ * @param {number} lower The lower bound.
+ * @param {number} upper The upper bound.
+ * @returns {number} Returns the random number.
+ */
+function baseRandom(lower, upper) {
+  return lower + nativeFloor(nativeRandom() * (upper - lower + 1));
+}
+
+module.exports = baseRandom;