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/date-fns/esm/fromUnixTime/index.d.ts

@@ -0,0 +1,4 @@
+// This file is generated automatically by `scripts/build/typings.js`. Please, don't change it.
+
+import { fromUnixTime } from 'date-fns'
+export default fromUnixTime

node_modules/date-fns/esm/fromUnixTime/index.js

@@ -0,0 +1,25 @@
+import toDate from "../toDate/index.js";
+import toInteger from "../_lib/toInteger/index.js";
+import requiredArgs from "../_lib/requiredArgs/index.js";
+/**
+ * @name fromUnixTime
+ * @category Timestamp Helpers
+ * @summary Create a date from a Unix timestamp.
+ *
+ * @description
+ * Create a date from a Unix timestamp (in seconds). Decimal values will be discarded.
+ *
+ * @param {Number} unixTime - the given Unix timestamp (in seconds)
+ * @returns {Date} the date
+ * @throws {TypeError} 1 argument required
+ *
+ * @example
+ * // Create the date 29 February 2012 11:45:05:
+ * const result = fromUnixTime(1330515905)
+ * //=> Wed Feb 29 2012 11:45:05
+ */
+export default function fromUnixTime(dirtyUnixTime) {
+  requiredArgs(1, arguments);
+  var unixTime = toInteger(dirtyUnixTime);
+  return toDate(unixTime * 1000);
+}

node_modules/date-fns/esm/fromUnixTime/index.js.flow

@@ -0,0 +1,52 @@
+// @flow
+// This file is generated automatically by `scripts/build/typings.js`. Please, don't change it.
+
+export type Interval = {
+  start: Date | number,
+  end: Date | number,
+}
+
+export type Locale = {
+  code?: string,
+  formatDistance?: (...args: Array<any>) => any,
+  formatRelative?: (...args: Array<any>) => any,
+  localize?: {
+    ordinalNumber: (...args: Array<any>) => any,
+    era: (...args: Array<any>) => any,
+    quarter: (...args: Array<any>) => any,
+    month: (...args: Array<any>) => any,
+    day: (...args: Array<any>) => any,
+    dayPeriod: (...args: Array<any>) => any,
+  },
+  formatLong?: {
+    date: (...args: Array<any>) => any,
+    time: (...args: Array<any>) => any,
+    dateTime: (...args: Array<any>) => any,
+  },
+  match?: {
+    ordinalNumber: (...args: Array<any>) => any,
+    era: (...args: Array<any>) => any,
+    quarter: (...args: Array<any>) => any,
+    month: (...args: Array<any>) => any,
+    day: (...args: Array<any>) => any,
+    dayPeriod: (...args: Array<any>) => any,
+  },
+  options?: {
+    weekStartsOn?: 0 | 1 | 2 | 3 | 4 | 5 | 6,
+    firstWeekContainsDate?: 1 | 2 | 3 | 4 | 5 | 6 | 7,
+  },
+}
+
+export type Duration = {
+  years?: number,
+  months?: number,
+  weeks?: number,
+  days?: number,
+  hours?: number,
+  minutes?: number,
+  seconds?: number,
+}
+
+export type Day = 0 | 1 | 2 | 3 | 4 | 5 | 6
+
+declare module.exports: (unixTime: number) => Date

node_modules/date-fns/esm/fromUnixTime/package.json

@@ -0,0 +1,4 @@
+{
+  "sideEffects": false,
+  "typings": "../../typings.d.ts"
+}