update docs

Author: JamesFreeman

docs/credential-storage.md

@@ -31,9 +31,32 @@ For the package to know which model you want to use, you will need to call the f
 use Webfox\Xero\Xero;
 use App\Models\User;
 
-Xero::useModelStore(User::find(1));
+Xero::useModelStore(Settings::first());
 ```
 
+If you need to resolve a model depending on some application state such as the authenticated user, this should be added to [a custom middleware](https://laravel.com/docs/11.x/middleware#defining-middleware) instead of the app service provider, e.g.
+
+<?php
+
+namespace App\Http\Middleware;
+
+use Closure;
+use Webfox\Xero\Xero;
+use Illuminate\Http\Request;
+
+class ConfigureXeroMiddleware
+{
+    public function handle(Request $request, Closure $next)
+    {
+        if ($request->user()) {
+            Xero::useModelStore($request->user()->currentTeam);
+        }
+
+        return $next($request);
+
+    }
+}
+
 By default, the package will use the `xero_credentials` field, Should you need to rename this field, you can do so by calling:
 
 ```php