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/eslint-plugin-import/memo-parser/LICENSE

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+The MIT License (MIT)
+
+Copyright (c) 2015 Ben Mosher
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

node_modules/eslint-plugin-import/memo-parser/README.md

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+# eslint-plugin-import/memo-parser
+
+## NOTE
+
+This used to improve performance, but as of ESLint 5 and v2 of this plugin, it seems to just consume a bunch of memory and slightly increase lint times.
+
+**Not recommended for use at this time!**
+
+This parser is just a memoizing wrapper around some actual parser.
+
+To configure, just add your _actual_ parser to the `parserOptions`, like so:
+
+```yaml
+parser: eslint-plugin-import/memo-parser
+# parser: babel-eslint
+
+parserOptions:
+  parser: babel-eslint
+  sourceType: module
+  ecmaVersion: 6
+```

node_modules/eslint-plugin-import/memo-parser/index.js

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+'use strict';
+
+const crypto = require('crypto');
+const moduleRequire = require('eslint-module-utils/module-require').default;
+const hashObject = require('eslint-module-utils/hash').hashObject;
+
+const cache = new Map();
+
+// must match ESLint default options or we'll miss the cache every time
+const parserOptions = {
+  loc: true,
+  range: true,
+  raw: true,
+  tokens: true,
+  comment: true,
+  attachComment: true,
+};
+
+exports.parse = function parse(content, options) {
+  options = { ...options, ...parserOptions };
+
+  if (!options.filePath) {
+    throw new Error('no file path provided!');
+  }
+
+  const keyHash = crypto.createHash('sha256');
+  keyHash.update(content);
+  hashObject(options, keyHash);
+
+  const key = keyHash.digest('hex');
+
+  let ast = cache.get(key);
+  if (ast != null) { return ast; }
+
+  const realParser = moduleRequire(options.parser);
+
+  ast = realParser.parse(content, options);
+  cache.set(key, ast);
+
+  return ast;
+};