feat: rating stars on recipe cards (Search, Explore)

New lib/recipe-ratings.ts helper batches avg score + review count for
a set of recipe ids in one grouped query, kept separate from the main
paginated/sorted search query rather than joining+grouping it directly
(would've forced grouping by every selected column). Wired into
/api/v1/search and the Explore page's trending/recent queries;
SearchResultCard renders the star only when a recipe has at least one
rating.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/app/(app)/explore/page.tsx

@@ -12,6 +12,7 @@ import {
   count,
 } from "@epicure/db";
 import { ExplorePageContent } from "@/components/search/explore-page-content";
+import { getAvgRatingsByRecipeId } from "@/lib/recipe-ratings";
 
 export const metadata: Metadata = {};
 
@@ -22,6 +23,8 @@ export type RecipeResult = {
   difficulty: string | null;
   prepMins: number | null;
   cookMins: number | null;
+  avgRating: number | null;
+  ratingCount: number;
 };
 
 export default async function ExplorePage({
@@ -73,8 +76,17 @@ export default async function ExplorePage({
     .orderBy(desc(recipes.createdAt))
     .limit(12);
 
-  const trending: RecipeResult[] = trendingRows.map(({ favoriteCount: _fc, ...r }) => r);
-  const recent: RecipeResult[] = recentRows;
+  const ratingByRecipe = await getAvgRatingsByRecipeId([
+    ...trendingRows.map((r) => r.id),
+    ...recentRows.map((r) => r.id),
+  ]);
+  const withRating = (r: { id: string }) => ({
+    avgRating: ratingByRecipe.get(r.id)?.avgRating ?? null,
+    ratingCount: ratingByRecipe.get(r.id)?.ratingCount ?? 0,
+  });
+
+  const trending: RecipeResult[] = trendingRows.map(({ favoriteCount: _fc, ...r }) => ({ ...r, ...withRating(r) }));
+  const recent: RecipeResult[] = recentRows.map((r) => ({ ...r, ...withRating(r) }));
 
   // Most-used tags across public recipes — shown as filter chips on the
   // search bar so browsing by tag doesn't require typing the exact word.