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/https-proxy-agent/dist/parse-proxy-response.js

@@ -0,0 +1,66 @@
+"use strict";
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
+Object.defineProperty(exports, "__esModule", { value: true });
+const debug_1 = __importDefault(require("debug"));
+const debug = debug_1.default('https-proxy-agent:parse-proxy-response');
+function parseProxyResponse(socket) {
+    return new Promise((resolve, reject) => {
+        // we need to buffer any HTTP traffic that happens with the proxy before we get
+        // the CONNECT response, so that if the response is anything other than an "200"
+        // response code, then we can re-play the "data" events on the socket once the
+        // HTTP parser is hooked up...
+        let buffersLength = 0;
+        const buffers = [];
+        function read() {
+            const b = socket.read();
+            if (b)
+                ondata(b);
+            else
+                socket.once('readable', read);
+        }
+        function cleanup() {
+            socket.removeListener('end', onend);
+            socket.removeListener('error', onerror);
+            socket.removeListener('close', onclose);
+            socket.removeListener('readable', read);
+        }
+        function onclose(err) {
+            debug('onclose had error %o', err);
+        }
+        function onend() {
+            debug('onend');
+        }
+        function onerror(err) {
+            cleanup();
+            debug('onerror %o', err);
+            reject(err);
+        }
+        function ondata(b) {
+            buffers.push(b);
+            buffersLength += b.length;
+            const buffered = Buffer.concat(buffers, buffersLength);
+            const endOfHeaders = buffered.indexOf('\r\n\r\n');
+            if (endOfHeaders === -1) {
+                // keep buffering
+                debug('have not received end of HTTP headers yet...');
+                read();
+                return;
+            }
+            const firstLine = buffered.toString('ascii', 0, buffered.indexOf('\r\n'));
+            const statusCode = +firstLine.split(' ')[1];
+            debug('got proxy server response: %o', firstLine);
+            resolve({
+                statusCode,
+                buffered
+            });
+        }
+        socket.on('error', onerror);
+        socket.on('close', onclose);
+        socket.on('end', onend);
+        read();
+    });
+}
+exports.default = parseProxyResponse;
+//# sourceMappingURL=parse-proxy-response.js.map