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/lighthouse/core/scripts/download-chrome.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+
+##
+# @license Copyright 2017 The Lighthouse Authors. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
+##
+
+# Download chrome inside of our CI env.
+
+set -euo pipefail
+
+unameOut="$(uname -s)"
+case "${unameOut}" in
+  Linux*)     machine=Linux;;
+  Darwin*)    machine=Mac;;
+  MINGW*)     machine=MinGw;;
+  *)          machine="UNKNOWN:${unameOut}"
+esac
+
+if [ "$machine" == "MinGw" ]; then
+  url="https://download-chromium.appspot.com/dl/Win?type=snapshots"
+elif [ "$machine" == "Linux" ]; then
+  url="https://download-chromium.appspot.com/dl/Linux_x64?type=snapshots"
+elif [ "$machine" == "Mac" ]; then
+  url="https://download-chromium.appspot.com/dl/Mac?type=snapshots"
+else
+  echo "unsupported platform"
+  exit 1
+fi
+
+if [ -e "$CHROME_PATH" ]; then
+  echo "cached chrome found"
+else
+  curl "$url" -Lo chrome.zip && unzip -q chrome.zip
+fi

node_modules/lighthouse/core/scripts/manual-chrome-launcher.js

@@ -0,0 +1,50 @@
+#!/usr/bin/env node
+
+
+/**
+ * @fileoverview Script to launch a clean Chrome instance on-demand.
+ *
+ * node core/scripts/manual-chrome-launcher.js
+ *
+ * Assuming Lighthouse is installed globally or `npm link`ed, use via:
+ *     chrome-debug
+ * Optionally enable extensions or pass a port, additional chrome flags, and/or a URL
+ *     chrome-debug --port=9222
+ *     chrome-debug http://goat.com
+ *     chrome-debug --show-paint-rects
+ *     chrome-debug --enable-extensions
+ */
+
+import {Launcher, launch} from 'chrome-launcher';
+
+const args = process.argv.slice(2);
+const chromeFlags = [];
+let startingUrl;
+let port;
+let ignoreDefaultFlags;
+
+if (args.length) {
+  const providedFlags = args.filter(flag => flag.startsWith('--'));
+
+  const portFlag = providedFlags.find(flag => flag.startsWith('--port='));
+  if (portFlag) port = parseInt(portFlag.replace('--port=', ''), 10);
+
+  const enableExtensions = !!providedFlags.find(flag => flag === '--enable-extensions');
+  // The basic pattern for enabling Chrome extensions
+  if (enableExtensions) {
+    ignoreDefaultFlags = true;
+    chromeFlags.push(...Launcher.defaultFlags().filter(flag => flag !== '--disable-extensions'));
+  }
+
+  chromeFlags.push(...providedFlags);
+  startingUrl = args.find(flag => !flag.startsWith('--'));
+}
+
+launch({
+  startingUrl,
+  port,
+  ignoreDefaultFlags,
+  chromeFlags,
+})
+// eslint-disable-next-line no-console
+.then(v => console.log(`✨  Chrome debugging port: ${v.port}`));