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/@webassemblyjs/ieee754/lib/index.js

@@ -0,0 +1,52 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.encodeF32 = encodeF32;
+exports.encodeF64 = encodeF64;
+exports.decodeF32 = decodeF32;
+exports.decodeF64 = decodeF64;
+exports.DOUBLE_PRECISION_MANTISSA = exports.SINGLE_PRECISION_MANTISSA = exports.NUMBER_OF_BYTE_F64 = exports.NUMBER_OF_BYTE_F32 = void 0;
+
+var _ieee = require("@xtuc/ieee754");
+
+/**
+ * According to https://webassembly.github.io/spec/binary/values.html#binary-float
+ * n = 32/8
+ */
+var NUMBER_OF_BYTE_F32 = 4;
+/**
+ * According to https://webassembly.github.io/spec/binary/values.html#binary-float
+ * n = 64/8
+ */
+
+exports.NUMBER_OF_BYTE_F32 = NUMBER_OF_BYTE_F32;
+var NUMBER_OF_BYTE_F64 = 8;
+exports.NUMBER_OF_BYTE_F64 = NUMBER_OF_BYTE_F64;
+var SINGLE_PRECISION_MANTISSA = 23;
+exports.SINGLE_PRECISION_MANTISSA = SINGLE_PRECISION_MANTISSA;
+var DOUBLE_PRECISION_MANTISSA = 52;
+exports.DOUBLE_PRECISION_MANTISSA = DOUBLE_PRECISION_MANTISSA;
+
+function encodeF32(v) {
+  var buffer = [];
+  (0, _ieee.write)(buffer, v, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
+  return buffer;
+}
+
+function encodeF64(v) {
+  var buffer = [];
+  (0, _ieee.write)(buffer, v, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
+  return buffer;
+}
+
+function decodeF32(bytes) {
+  var buffer = new Uint8Array(bytes);
+  return (0, _ieee.read)(buffer, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
+}
+
+function decodeF64(bytes) {
+  var buffer = new Uint8Array(bytes);
+  return (0, _ieee.read)(buffer, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
+}