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/core-js-pure/features/function/bind.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/bind');

node_modules/core-js-pure/features/function/demethodize.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/demethodize');

node_modules/core-js-pure/features/function/has-instance.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/has-instance');

node_modules/core-js-pure/features/function/index.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function');

node_modules/core-js-pure/features/function/is-callable.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/is-callable');

node_modules/core-js-pure/features/function/is-constructor.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/is-constructor');

node_modules/core-js-pure/features/function/metadata.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/metadata');

node_modules/core-js-pure/features/function/name.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/name');

node_modules/core-js-pure/features/function/un-this.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../full/function/un-this');

node_modules/core-js-pure/features/function/virtual/bind.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../../full/function/virtual/bind');

node_modules/core-js-pure/features/function/virtual/demethodize.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../../full/function/virtual/demethodize');

node_modules/core-js-pure/features/function/virtual/index.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../../full/function/virtual');

node_modules/core-js-pure/features/function/virtual/un-this.js

@@ -0,0 +1,2 @@
+'use strict';
+module.exports = require('../../../full/function/virtual/un-this');