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/check-node-version/cli.js

@@ -0,0 +1,177 @@
+"use strict";
+
+const fs = require("fs");
+const path = require("path");
+
+const chalk = require("chalk");
+const minimist = require("minimist");
+const semver = require('semver');
+
+const check = require(".");
+const tools = require("./tools");
+
+
+const argv = minimist(process.argv.slice(2), {
+  alias: {
+    "print": "p",
+    "help": "h",
+  },
+  boolean: [
+    "print",
+    "help",
+    "volta",
+    "package",
+  ],
+  string: [
+    "node",
+    "npm",
+    "npx",
+    "yarn",
+    "pnpm",
+  ],
+  unknown: function (arg) {
+    console.error(`Unknown option: ${arg}`);
+    process.exit(1);
+  }
+});
+
+if (argv.help) {
+  const usage = fs.readFileSync(path.join(__dirname, "usage.txt"), {
+    encoding: "utf8",
+  });
+
+  process.stdout.write(usage);
+  process.exit(0);
+}
+
+let options;
+if (argv.package) {
+  options = optionsFromPackage();
+} else if (argv.volta) {
+  options = optionsFromVolta();
+} else {
+  options = optionsFromCommandLine();
+}
+
+check(options, (err, result) => {
+  if (err) {
+    throw err;
+  }
+
+  printVersions(result, argv.print);
+  process.exit(result.isSatisfied ? 0 : 1);
+});
+
+
+//
+
+
+function optionsFromCommandLine() {
+  return Object.keys(tools).reduce((memo, name) => ({
+    ...memo,
+    [name]: argv[name],
+  }), {});
+}
+
+function optionsFromPackage() {
+  let packageJson;
+
+  try {
+    packageJson = require(path.join(process.cwd(), 'package.json'));
+  } catch (e) {
+    console.log('Error: When running with --package, a package.json file is expected in the current working directory');
+    console.log('Current working directory is: ' + process.cwd());
+
+    process.exit(1);
+  }
+
+  if (!packageJson.engines) {
+    console.log('Error: When running with --package, your package.json is expected to contain the "engines" key');
+    console.log('See https://docs.npmjs.com/files/package.json#engines for the supported syntax');
+
+    process.exit(1);
+  }
+
+  return Object.keys(tools).reduce((memo, name) => ({
+    ...memo,
+    [name]: packageJson.engines[name],
+  }), {});
+}
+
+function optionsFromVolta() {
+  let packageJson;
+
+  try {
+    packageJson = require(path.join(process.cwd(), 'package.json'));
+  } catch (e) {
+    console.log('Error: When running with --volta, a package.json file is expected in the current working directory');
+    console.log('Current working directory is: ' + process.cwd());
+
+    process.exit(1);
+  }
+
+  if (!packageJson.volta) {
+    console.log('Error: When running with --volta, your package.json is expected to contain the "volta" key');
+    console.log('See https://docs.volta.sh/guide/understanding#pinning-node-engines');
+
+    process.exit(1);
+  }
+  console.log(packageJson.volta);
+
+  return Object.keys(tools).reduce((memo, name) => ({
+    ...memo,
+    [name]: packageJson.volta[name],
+  }), {});
+}
+
+//
+
+
+function printVersions(result, print) {
+  Object.keys(result.versions).forEach(name => {
+    const info = result.versions[name];
+    const isSatisfied = info.isSatisfied;
+
+    // print installed version
+    if (print || !isSatisfied) {
+      printInstalledVersion(name, info);
+    }
+
+    if (isSatisfied) return;
+
+    // report any non-compliant versions
+    const { raw, range } = info.wanted;
+
+    console.error(chalk.red(`Wanted ${name} version ` + chalk.bold(`${raw} (${range})`)));
+
+    console.log(chalk.yellow.bold(
+      tools[name]
+      .getInstallInstructions(
+        semver.minVersion(info.wanted)
+      )
+    ));
+  });
+}
+
+function printInstalledVersion(name, { version, isSatisfied, invalid, notfound }) {
+  let versionNote = "";
+
+  if (version) {
+    versionNote = name + ": " + chalk.bold(version);
+  }
+
+  if (invalid) {
+    versionNote = name + ": " + chalk.bold("given version not semver-compliant");
+  }
+
+  if (notfound) {
+    versionNote = name + ": not found";
+  }
+
+  if (isSatisfied) {
+    if (version) console.log(versionNote);
+    else console.log(chalk.gray(versionNote));
+  } else {
+    console.log(chalk.red(versionNote));
+  }
+}