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/http-proxy-middleware/dist/router.js

@@ -0,0 +1,46 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.getTarget = void 0;
+const isPlainObj = require("is-plain-obj");
+const logger_1 = require("./logger");
+const logger = (0, logger_1.getInstance)();
+async function getTarget(req, config) {
+    let newTarget;
+    const router = config.router;
+    if (isPlainObj(router)) {
+        newTarget = getTargetFromProxyTable(req, router);
+    }
+    else if (typeof router === 'function') {
+        newTarget = await router(req);
+    }
+    return newTarget;
+}
+exports.getTarget = getTarget;
+function getTargetFromProxyTable(req, table) {
+    let result;
+    const host = req.headers.host;
+    const path = req.url;
+    const hostAndPath = host + path;
+    for (const [key] of Object.entries(table)) {
+        if (containsPath(key)) {
+            if (hostAndPath.indexOf(key) > -1) {
+                // match 'localhost:3000/api'
+                result = table[key];
+                logger.debug('[HPM] Router table match: "%s"', key);
+                break;
+            }
+        }
+        else {
+            if (key === host) {
+                // match 'localhost:3000'
+                result = table[key];
+                logger.debug('[HPM] Router table match: "%s"', host);
+                break;
+            }
+        }
+    }
+    return result;
+}
+function containsPath(v) {
+    return v.indexOf('/') > -1;
+}