Implement progressive enhancement for universal search with context-aware filtering

Add comprehensive search solution that works across all recipe pages with proper fallbacks. Features include universal API endpoint, context-aware filtering (category/tag/icon/season/favorites), and progressive enhancement with form submission fallback for no-JS users.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/routes/api/rezepte/search/+server.ts

@@ -0,0 +1,74 @@
+import { json, type RequestHandler } from '@sveltejs/kit';
+import type { BriefRecipeType } from '../../../../types/types';
+import { Recipe } from '../../../../models/Recipe';
+import { dbConnect, dbDisconnect } from '../../../../utils/db';
+
+export const GET: RequestHandler = async ({ url, locals }) => {
+  await dbConnect();
+  
+  const query = url.searchParams.get('q')?.toLowerCase().trim() || '';
+  const category = url.searchParams.get('category');
+  const tag = url.searchParams.get('tag');
+  const icon = url.searchParams.get('icon');
+  const season = url.searchParams.get('season');
+  const favoritesOnly = url.searchParams.get('favorites') === 'true';
+  
+  try {
+    // Build base query
+    let dbQuery: any = {};
+    
+    // Apply filters based on context
+    if (category) {
+      dbQuery.category = category;
+    }
+    
+    if (tag) {
+      dbQuery.tags = { $in: [tag] };
+    }
+    
+    if (icon) {
+      dbQuery.icon = icon;
+    }
+    
+    if (season) {
+      const seasonNum = parseInt(season);
+      if (!isNaN(seasonNum)) {
+        dbQuery.season = { $in: [seasonNum] };
+      }
+    }
+    
+    // Get all recipes matching base filters
+    let recipes = await Recipe.find(dbQuery, 'name short_name tags category icon description season dateModified').lean() as BriefRecipeType[];
+    
+    // Handle favorites filter
+    if (favoritesOnly && locals.session?.user) {
+      const User = (await import('../../../../models/User')).User;
+      const user = await User.findById(locals.session.user.id);
+      if (user && user.favoriteRecipes) {
+        const favoriteShortNames = user.favoriteRecipes;
+        recipes = recipes.filter(recipe => favoriteShortNames.includes(recipe.short_name));
+      } else {
+        recipes = [];
+      }
+    }
+    
+    // Apply text search if query provided
+    if (query) {
+      const searchTerms = query.normalize('NFD').replace(/\p{Diacritic}/gu, "").split(" ");
+      
+      recipes = recipes.filter(recipe => {
+        const searchString = `${recipe.name} ${recipe.description || ''} ${recipe.tags?.join(' ') || ''}`.toLowerCase()
+          .normalize('NFD').replace(/\p{Diacritic}/gu, "").replace(/­|­/g, '');
+        
+        return searchTerms.every(term => searchString.includes(term));
+      });
+    }
+    
+    await dbDisconnect();
+    return json(JSON.parse(JSON.stringify(recipes)));
+    
+  } catch (error) {
+    await dbDisconnect();
+    return json({ error: 'Search failed' }, { status: 500 });
+  }
+};