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/stylis/package.json

@@ -0,0 +1,167 @@
+{
+  "name": "stylis",
+  "version": "4.2.0",
+  "license": "MIT",
+  "description": "A Light–weight CSS Preprocessor",
+  "homepage": "https://github.com/thysultan/stylis.js",
+  "author": "Sultan Tarimo <sultantarimo@me.com>",
+  "repository": "https://github.com/thysultan/stylis.js",
+  "bugs": "https://github.com/thysultan/stylis.js/issues",
+  "sideEffects": false,
+  "type": "module",
+  "main": "dist/umd/stylis.js",
+  "module": "dist/stylis.mjs",
+  "react-native": "./index.js",
+  "exports": {
+    ".": {
+      "import": "./index.js",
+      "require": "./dist/umd/stylis.js"
+    },
+    "./package.json": "./package.json"
+  },
+  "files": [
+    "index.js",
+    "dist/",
+    "src/"
+  ],
+  "scripts": {
+    "lint": "eslint ./",
+    "pretest": "npm run lint && npm run build",
+    "test": "nyc npm run spec",
+    "spec": "mocha --harmony --require esm script/setup.js --recursive test",
+    "prebuild": "rimraf dist",
+    "build": "rollup --config script/build.js --configSrc ./",
+    "start": "npm run build -- --watch",
+    "prepare": "npm run build",
+    "postversion": "git push --follow-tags && npm publish",
+    "release-major": "npm version major -m '%s'",
+    "release-minor": "npm version minor -m '%s'",
+    "release-patch": "npm version patch -m '%s'"
+  },
+  "devDependencies": {
+    "chai": "4.3.4",
+    "eslint": "6.8.0",
+    "esm": "3.2.25",
+    "mocha": "9.1.1",
+    "nyc": "15.1.0",
+    "rimraf": "3.0.2",
+    "rollup": "1.28.0",
+    "rollup-plugin-size": "0.2.1",
+    "rollup-plugin-terser": "5.1.3",
+    "stylis": "./"
+  },
+  "nyc": {
+    "temp-dir": "./coverage/.nyc_output",
+    "exclude": [
+      "**/dist/",
+      "**/test/",
+      "**/script/"
+    ],
+    "reporter": [
+      "lcov",
+      "text"
+    ]
+  },
+  "esm": {
+    "cjs": true,
+    "cache": false
+  },
+  "eslintIgnore": [
+    "script/",
+    "test/",
+    "dist/",
+    "docs/"
+  ],
+  "eslintConfig": {
+    "env": {
+      "commonjs": true,
+      "browser": true,
+      "node": true,
+      "es6": true
+    },
+    "extends": "eslint:recommended",
+    "parserOptions": {
+      "ecmaVersion": 7,
+      "sourceType": "module",
+      "ecmaFeatures": {
+        "impliedStrict": true
+      }
+    },
+    "rules": {
+      "indent": [
+        "error",
+        "tab",
+        {
+          "SwitchCase": 1
+        }
+      ],
+      "linebreak-style": [
+        "error",
+        "unix"
+      ],
+      "quotes": [
+        "error",
+        "single"
+      ],
+      "semi": [
+        "error",
+        "never"
+      ],
+      "no-cond-assign": [
+        "off"
+      ],
+      "no-redeclare": [
+        "off"
+      ],
+      "no-fallthrough": [
+        "off"
+      ],
+      "no-console": [
+        "off"
+      ],
+      "no-unsafe-finally": [
+        "off"
+      ],
+      "no-shadow-restricted-names": [
+        "error"
+      ],
+      "no-whitespace-before-property": [
+        "error"
+      ],
+      "no-else-return": [
+        "error"
+      ],
+      "eol-last": [
+        "error"
+      ],
+      "func-call-spacing": [
+        "error",
+        "never"
+      ],
+      "brace-style": [
+        "error",
+        "1tbs",
+        {
+          "allowSingleLine": true
+        }
+      ],
+      "require-jsdoc": [
+        "error",
+        {
+          "require": {
+            "FunctionDeclaration": true
+          }
+        }
+      ],
+      "no-trailing-spaces": [
+        "error",
+        {
+          "skipBlankLines": true
+        }
+      ],
+      "no-constant-condition": [
+        "off"
+      ]
+    }
+  }
+}