perf: drop all_brief fetch from favorites page

Favorites page fetched both /favorites/recipes and /items/all_brief, then
stitched isFavorite flags onto allRecipes so Search could filter across
the full catalogue. But Search is invoked with favoritesOnly={true} and
hideFavoritesFilter (so it's pinned on), so it only ever returns matches
that are already in the favorites list — allRecipes was dead weight.

- drop allRes / allRecipes / favoriteIds / allRecipesWithFavorites
- Search now receives data.favorites directly
- filteredFavorites filters data.favorites by matchedRecipeIds
- use locals.session ?? locals.auth() to reuse the hook's auth lookup

src/routes/[recipeLang=recipeLang]/favorites/+page.server.ts

@@ -3,7 +3,7 @@ import { redirect } from '@sveltejs/kit';
 
 export const load: PageServerLoad = async ({ fetch, locals, params }) => {
     const apiBase = `/api/${params.recipeLang}`;
-    const session = await locals.auth();
+    const session = locals.session ?? await locals.auth();
 
     if (!session?.user?.nickname) {
         const callbackUrl = encodeURIComponent(`/${params.recipeLang}/favorites`);
@@ -11,44 +11,25 @@ export const load: PageServerLoad = async ({ fetch, locals, params }) => {
     }
 
     try {
-        const [res, allRes] = await Promise.all([
-            fetch(`${apiBase}/favorites/recipes`),
-            fetch(`${apiBase}/items/all_brief`)
-        ]);
+        const res = await fetch(`${apiBase}/favorites/recipes`);
 
         if (!res.ok) {
             return {
                 favorites: [],
-                allRecipes: [],
                 error: 'Failed to load favorites'
             };
         }
 
-        const [favorites, allRecipes] = await Promise.all([res.json(), allRes.json()]);
-
-        // Mark all favorites with isFavorite flag for filter compatibility
-        const favoritesWithFlag = favorites.map((recipe: any) => ({
-            ...recipe,
-            isFavorite: true
-        }));
-
-        // Get favorite IDs for marking in allRecipes
-        const favoriteIds = new Set(favoritesWithFlag.map((r: any) => r._id));
-        const allRecipesWithFavorites = allRecipes.map((recipe: any) => ({
-            ...recipe,
-            isFavorite: favoriteIds.has(recipe._id)
-        }));
+        const favorites = await res.json();
 
         return {
-            favorites: favoritesWithFlag,
-            allRecipes: allRecipesWithFavorites,
+            favorites: favorites.map((recipe: any) => ({ ...recipe, isFavorite: true })),
             session
         };
     } catch (e) {
         return {
             favorites: [],
-            allRecipes: [],
             error: 'Failed to load favorites'
         };
     }
-};
+};

src/routes/[recipeLang=recipeLang]/favorites/+page.svelte

@@ -33,12 +33,12 @@
 
     function handleSearchResults(ids: Set<string>, categories: Set<string>) {
         matchedRecipeIds = ids;
-        hasActiveSearch = ids.size < (data.allRecipes?.length || data.favorites.length);
+        hasActiveSearch = ids.size < data.favorites.length;
     }
 
     const filteredFavorites = $derived.by(() => {
         if (!hasActiveSearch) return data.favorites;
-        return data.allRecipes.filter((r: any) => matchedRecipeIds.has(r._id));
+        return data.favorites.filter((r: any) => matchedRecipeIds.has(r._id));
     });
 </script>
 
@@ -93,7 +93,7 @@
 
 <p class="to-try-link"><a href="/{data.recipeLang}/to-try">{labels.toTry} &rarr;</a></p>
 
-<Search favoritesOnly={true} lang={data.lang} recipes={data.allRecipes || data.favorites} isLoggedIn={!!data.session?.user} onSearchResults={handleSearchResults}></Search>
+<Search favoritesOnly={true} lang={data.lang} recipes={data.favorites} isLoggedIn={!!data.session?.user} onSearchResults={handleSearchResults}></Search>
 
 {#if data.error}
     <p class="empty-state">{labels.errorLoading} {data.error}</p>