Optimierung 5.3 (Teil 2): Category::localizedName()

Name aus der locale-gefiltert geladenen Uebersetzung mit #id-Fallback als
Model-Methode. Ersetzt die identische Inline-Logik an 4 Stellen (Footer-Codes
und Kategorien jeweils create/edit).

Test: CategoryLocalizedNameTest.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/Feature/CategoryLocalizedNameTest.php

@@ -0,0 +1,18 @@
+<?php
+
+use App\Models\Category;
+
+test('localizedName returns the loaded translation name', function () {
+    $category = Category::factory()->withTranslations()->create();
+    $category->load(['translations' => fn ($query) => $query->where('locale', 'de')]);
+
+    $expected = $category->translations->first()->name;
+
+    expect($category->localizedName())->toBe($expected);
+});
+
+test('localizedName falls back to the id when no translation is loaded', function () {
+    $category = Category::factory()->create();
+
+    expect($category->localizedName())->toBe('#'.$category->id);
+});