Add BackedEnum Support to RoleOrPermissionMiddleware

[imhayatunnabi]

I was working on a multi-tenant inventory which has multiple roles and permissions where we decided to modernize our codebase by migrating from string-based permissions to PHP 8.1+ BackedEnums for better type safety and IDE autocompletion. We created a comprehensive enum structure:

enum Permission: string
{
    case VIEW_DASHBOARD = 'view dashboard';
    case EDIT_ARTICLES = 'edit articles';
    case DELETE_ARTICLES = 'delete articles';
    case MANAGE_USERS = 'manage users';
    case PUBLISH_CONTENT = 'publish content';
}

enum Role: string
{
    case ADMIN = 'admin';
    case EDITOR = 'editor';
    case WRITER = 'writer';
}

Everything was going smoothly - we updated our routes to use enums with PermissionMiddleware and RoleMiddleware, and they worked perfectly:

// This worked great
Route::middleware(['permission:'.Permission::EDIT_ARTICLES->value])
    ->group(function () {
        // ...
    });

// This also worked
Route::middleware([PermissionMiddleware::using(Permission::EDIT_ARTICLES)])
    ->group(function () {
        // ...
    });

Then the problem hit: We had several routes that needed to check for either a role or a permission (e.g., "allow access if user is an admin OR has edit permission"). We tried to use RoleOrPermissionMiddleware with our enums:

// This failed silently - the middleware didn't recognize the enum
Route::middleware([
    RoleOrPermissionMiddleware::using(Permission::EDIT_ARTICLES)
])->group(function () {
    // Users were getting 403 errors even when they had the permission!
});

Here I have added complete BackedEnum which is a PHP built-in interface in PHP 8.1+ versions to support to RoleOrPermissionMiddleware, making it consistent with the other middleware classes in the package.