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/table/dist/src/utils.d.ts

@@ -0,0 +1,9 @@
+import type { SpanningCellConfig } from './types/api';
+import type { BaseConfig, CellCoordinates, RangeCoordinate } from './types/internal';
+export declare const sequence: (start: number, end: number) => number[];
+export declare const sumArray: (array: number[]) => number;
+export declare const extractTruncates: (config: BaseConfig) => number[];
+export declare const flatten: <T>(array: T[][]) => T[];
+export declare const calculateRangeCoordinate: (spanningCellConfig: SpanningCellConfig) => RangeCoordinate;
+export declare const areCellEqual: (cell1: CellCoordinates, cell2: CellCoordinates) => boolean;
+export declare const isCellInRange: (cell: CellCoordinates, { topLeft, bottomRight }: RangeCoordinate) => boolean;