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/pure-rand/lib/distribution/UnsafeUniformArrayIntDistribution.js

@@ -0,0 +1,12 @@
+"use strict";
+exports.__esModule = true;
+exports.unsafeUniformArrayIntDistribution = void 0;
+var ArrayInt_1 = require("./internals/ArrayInt");
+var UnsafeUniformArrayIntDistributionInternal_1 = require("./internals/UnsafeUniformArrayIntDistributionInternal");
+function unsafeUniformArrayIntDistribution(from, to, rng) {
+    var rangeSize = (0, ArrayInt_1.trimArrayIntInplace)((0, ArrayInt_1.addOneToPositiveArrayInt)((0, ArrayInt_1.substractArrayIntToNew)(to, from)));
+    var emptyArrayIntData = rangeSize.data.slice(0);
+    var g = (0, UnsafeUniformArrayIntDistributionInternal_1.unsafeUniformArrayIntDistributionInternal)(emptyArrayIntData, rangeSize.data, rng);
+    return (0, ArrayInt_1.trimArrayIntInplace)((0, ArrayInt_1.addArrayIntToNew)({ sign: 1, data: g }, from));
+}
+exports.unsafeUniformArrayIntDistribution = unsafeUniformArrayIntDistribution;