feat: add untranslated recipes page for recipe admins

Add new page at /rezepte/untranslated for recipe admins to view and manage recipes without approved English translations. Includes translation status tracking, statistics dashboard, and visual badges.

Changes:
- Add API endpoint to fetch recipes without approved translations
- Create untranslated recipes page with auth checks for rezepte_users group
- Add translation status badges to Card component (pending, needs_update, none)
- Add database index on translations.en.translationStatus for performance
- Create layout for /rezepte route with header navigation
- Add "Unübersetzt" link to navigation for authorized users

src/routes/api/rezepte/translate/untranslated/+server.ts

@@ -0,0 +1,48 @@
+import { json, type RequestHandler, error } from '@sveltejs/kit';
+import { Recipe } from '../../../../../models/Recipe';
+import { dbConnect } from '../../../../../utils/db';
+
+export const GET: RequestHandler = async ({ locals }) => {
+	const session = await locals.auth();
+
+	if (!session?.user?.nickname) {
+		throw error(401, 'Anmeldung erforderlich');
+	}
+
+	if (!session.user.groups?.includes('rezepte_users')) {
+		throw error(403, 'Zugriff verweigert');
+	}
+
+	await dbConnect();
+
+	try {
+		// Find recipes without approved English translation
+		const untranslated = await Recipe.find({
+			$or: [
+				{ 'translations.en': { $exists: false } },
+				{ 'translations.en.translationStatus': { $ne: 'approved' } }
+			]
+		}, 'name short_name category icon description tags season dateModified translations.en.translationStatus')
+		.sort({ dateModified: 1 }) // Oldest first - highest priority
+		.lean();
+
+		// Transform to include translationStatus at top level for easier UI handling
+		const result = untranslated.map(recipe => ({
+			_id: recipe._id,
+			name: recipe.name,
+			short_name: recipe.short_name,
+			category: recipe.category,
+			icon: recipe.icon,
+			description: recipe.description,
+			tags: recipe.tags || [],
+			season: recipe.season || [],
+			dateModified: recipe.dateModified,
+			translationStatus: recipe.translations?.en?.translationStatus || undefined
+		}));
+
+		return json(JSON.parse(JSON.stringify(result)));
+	} catch (e) {
+		console.error('Error fetching untranslated recipes:', e);
+		throw error(500, 'Fehler beim Laden der unübersetzten Rezepte');
+	}
+};