align backend auth patterns

backend/app/Shared/Http/RequestInput.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Shared\Http;
+
+use Illuminate\Http\Request;
+
+class RequestInput
+{
+    public function __construct(private Request $request) {}
+
+    public function string(string $key): ?string
+    {
+        $value = $this->request->input($key);
+        if (is_string($value)) {
+            return $value;
+        }
+        if (is_int($value) || is_float($value) || is_bool($value)) {
+            return (string) $value;
+        }
+
+        return null;
+    }
+}