fix: add category and favorites filters to all recipe pages

- Move categories logic into Search component for centralization
- Add isLoggedIn prop to SeasonLayout and IconLayout components
- Fix FilterPanel CSS to properly handle hidden favorites filter
- Fix FavoritesFilter to trigger onToggle when checkbox changes
- Update Search effect to track all filter states (category, tags, icon, season, favorites)
- Hide favorites filter on favorites page while maintaining proper grid layout
- All filters now work consistently across entire site

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

@@ -35,7 +35,7 @@
 	}
 </style>
 <h1>{label} <q>{data.category}</q>:</h1>
-<Search category={data.category} lang={data.lang} recipes={data.recipes} onSearchResults={handleSearchResults}></Search>
+<Search category={data.category} lang={data.lang} recipes={data.recipes} isLoggedIn={!!data.session?.user} onSearchResults={handleSearchResults}></Search>
 <section>
 <Recipes>
 	{#each rand_array(filteredRecipes) as recipe}