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/pump/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "pump",
+  "version": "3.0.4",
+  "repository": "git://github.com/mafintosh/pump.git",
+  "license": "MIT",
+  "description": "pipe streams together and close all of them if one of them closes",
+  "browser": {
+    "fs": false
+  },
+  "imports": {
+    "fs": {
+      "bare": "./empty.js",
+      "default": "fs"
+    }
+  },
+  "keywords": [
+    "streams",
+    "pipe",
+    "destroy",
+    "callback"
+  ],
+  "author": "Mathias Buus Madsen <mathiasbuus@gmail.com>",
+  "dependencies": {
+    "end-of-stream": "^1.1.0",
+    "once": "^1.3.1"
+  },
+  "scripts": {
+    "test": "node test-browser.js && node test-node.js"
+  }
+}