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/stylelint/lib/rules/value-list-comma-newline-after/index.js

@@ -0,0 +1,103 @@
+'use strict';
+
+const declarationValueIndex = require('../../utils/declarationValueIndex');
+const getDeclarationValue = require('../../utils/getDeclarationValue');
+const ruleMessages = require('../../utils/ruleMessages');
+const setDeclarationValue = require('../../utils/setDeclarationValue');
+const validateOptions = require('../../utils/validateOptions');
+const valueListCommaWhitespaceChecker = require('../valueListCommaWhitespaceChecker');
+const whitespaceChecker = require('../../utils/whitespaceChecker');
+
+const ruleName = 'value-list-comma-newline-after';
+
+const messages = ruleMessages(ruleName, {
+	expectedAfter: () => 'Expected newline after ","',
+	expectedAfterMultiLine: () => 'Expected newline after "," in a multi-line list',
+	rejectedAfterMultiLine: () => 'Unexpected whitespace after "," in a multi-line list',
+});
+
+const meta = {
+	url: 'https://stylelint.io/user-guide/rules/value-list-comma-newline-after',
+	fixable: true,
+};
+
+/** @type {import('stylelint').Rule} */
+const rule = (primary, _secondaryOptions, context) => {
+	const checker = whitespaceChecker('newline', primary, messages);
+
+	return (root, result) => {
+		const validOptions = validateOptions(result, ruleName, {
+			actual: primary,
+			possible: ['always', 'always-multi-line', 'never-multi-line'],
+		});
+
+		if (!validOptions) {
+			return;
+		}
+
+		/** @type {Map<import('postcss').Declaration, number[]> | undefined} */
+		let fixData;
+
+		valueListCommaWhitespaceChecker({
+			root,
+			result,
+			locationChecker: checker.afterOneOnly,
+			checkedRuleName: ruleName,
+			fix: context.fix
+				? (declNode, index) => {
+						const valueIndex = declarationValueIndex(declNode);
+
+						if (index <= valueIndex) {
+							return false;
+						}
+
+						fixData = fixData || new Map();
+						const commaIndices = fixData.get(declNode) || [];
+
+						commaIndices.push(index);
+						fixData.set(declNode, commaIndices);
+
+						return true;
+				  }
+				: null,
+			determineIndex: (declString, match) => {
+				const nextChars = declString.substring(match.endIndex, declString.length);
+
+				// If there's a // comment, that means there has to be a newline
+				// ending the comment so we're fine
+				if (/^[ \t]*\/\//.test(nextChars)) {
+					return false;
+				}
+
+				// If there are spaces and then a comment begins, look for the newline
+				return /^[ \t]*\/\*/.test(nextChars)
+					? declString.indexOf('*/', match.endIndex) + 1
+					: match.startIndex;
+			},
+		});
+
+		if (fixData) {
+			for (const [decl, commaIndices] of fixData.entries()) {
+				for (const index of commaIndices.sort((a, b) => a - b).reverse()) {
+					const value = getDeclarationValue(decl);
+					const valueIndex = index - declarationValueIndex(decl);
+					const beforeValue = value.slice(0, valueIndex + 1);
+					let afterValue = value.slice(valueIndex + 1);
+
+					if (primary.startsWith('always')) {
+						afterValue = context.newline + afterValue;
+					} else if (primary.startsWith('never-multi-line')) {
+						afterValue = afterValue.replace(/^\s*/, '');
+					}
+
+					setDeclarationValue(decl, beforeValue + afterValue);
+				}
+			}
+		}
+	};
+};
+
+rule.ruleName = ruleName;
+rule.messages = messages;
+rule.meta = meta;
+module.exports = rule;