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/minimist-options/readme.md

@@ -0,0 +1,112 @@
+# minimist-options ![test](https://github.com/vadimdemedes/minimist-options/workflows/test/badge.svg) 
+
+> Write options for [minimist](https://npmjs.org/package/minimist) and [yargs](https://npmjs.org/package/yargs) in a comfortable way.
+> Supports string, boolean, number and array options.
+
+## Installation
+
+```
+$ npm install --save minimist-options
+```
+
+## Usage
+
+```js
+const buildOptions = require('minimist-options');
+const minimist = require('minimist');
+
+const options = buildOptions({
+	name: {
+		type: 'string',
+		alias: 'n',
+		default: 'john'
+	},
+
+	force: {
+		type: 'boolean',
+		alias: ['f', 'o'],
+		default: false
+	},
+
+	score: {
+		type: 'number',
+		alias: 's',
+		default: 0
+	},
+
+	arr: {
+		type: 'array',
+		alias: 'a',
+		default: []
+	},
+
+	strings: {
+		type: 'string-array',
+		alias: 's',
+		default: ['a', 'b']
+	},
+
+	booleans: {
+		type: 'boolean-array',
+		alias: 'b',
+		default: [true, false]
+	},
+
+	numbers: {
+		type: 'number-array',
+		alias: 'n',
+		default: [0, 1]
+	},
+
+	published: 'boolean',
+
+	// Special option for positional arguments (`_` in minimist)
+	arguments: 'string'
+});
+
+const args = minimist(process.argv.slice(2), options);
+```
+
+instead of:
+
+```js
+const minimist = require('minimist');
+
+const options = {
+	string: ['name', '_'],
+	number: ['score'],
+	array: [
+		'arr',
+		{key: 'strings', string: true},
+		{key: 'booleans', boolean: true},
+		{key: 'numbers', number: true}
+	],
+	boolean: ['force', 'published'],
+	alias: {
+		n: 'name',
+		f: 'force',
+		s: 'score',
+		a: 'arr'
+	},
+	default: {
+		name: 'john',
+		f: false,
+		score: 0,
+		arr: []
+	}
+};
+
+const args = minimist(process.argv.slice(2), options);
+```
+
+## Array options
+
+The `array` types are only supported by [yargs](https://npmjs.org/package/yargs).
+
+[minimist](https://npmjs.org/package/minimist) does _not_ explicitly support array type options. If you set an option multiple times, it will indeed yield an array of values. However, if you only set it once, it will simply give the value as is, without wrapping it in an array. Thus, effectively ignoring `{type: 'array'}`.
+
+`{type: 'array'}` is shorthand for `{type: 'string-array'}`. To have values coerced to `boolean` or `number`, use `boolean-array` or `number-array`, respectively.
+
+## License
+
+MIT © [Vadim Demedes](https://vadimdemedes.com)