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/src/index.js

@@ -0,0 +1,47 @@
+// @flow
+
+import { write, read } from "@xtuc/ieee754";
+
+/**
+ * According to https://webassembly.github.io/spec/binary/values.html#binary-float
+ * n = 32/8
+ */
+export const NUMBER_OF_BYTE_F32 = 4;
+
+/**
+ * According to https://webassembly.github.io/spec/binary/values.html#binary-float
+ * n = 64/8
+ */
+export const NUMBER_OF_BYTE_F64 = 8;
+
+export const SINGLE_PRECISION_MANTISSA = 23;
+
+export const DOUBLE_PRECISION_MANTISSA = 52;
+
+export function encodeF32(v: number): Array<number> {
+  const buffer = [];
+
+  write(buffer, v, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
+
+  return buffer;
+}
+
+export function encodeF64(v: number): Array<number> {
+  const buffer = [];
+
+  write(buffer, v, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
+
+  return buffer;
+}
+
+export function decodeF32(bytes: Array<Byte>): number {
+  const buffer = new Uint8Array(bytes);
+
+  return read(buffer, 0, true, SINGLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F32);
+}
+
+export function decodeF64(bytes: Array<Byte>): number {
+  const buffer = new Uint8Array(bytes);
+
+  return read(buffer, 0, true, DOUBLE_PRECISION_MANTISSA, NUMBER_OF_BYTE_F64);
+}