Ajoute une image de couverture sur les cards de jeu

- Champ `cover` dans lib/games.ts
- Branché sur la card home, la liste des jeux et le hero page projet
- Fallback placeholder logo si pas d'image

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/games/[slug]/page.tsx

@@ -65,15 +65,26 @@ export default async function GamePage({ params }: Props) {
       />
       {/* HERO */}
       <section className="relative aspect-[21/9] sm:aspect-[21/8] bg-surface border-b border-border overflow-hidden">
-        <div className="absolute inset-0 flex items-center justify-center">
+        {game.cover ? (
           <Image
-            src="/image/Studio/Logo Flat.png"
-            alt=""
-            width={220}
-            height={148}
-            className="opacity-20"
+            src={game.cover}
+            alt={game.title}
+            fill
+            priority
+            sizes="100vw"
+            className="object-cover"
           />
-        </div>
+        ) : (
+          <div className="absolute inset-0 flex items-center justify-center">
+            <Image
+              src="/image/Studio/Logo Flat.png"
+              alt=""
+              width={220}
+              height={148}
+              className="opacity-20"
+            />
+          </div>
+        )}
         <div className="absolute inset-0 bg-gradient-to-t from-background via-background/40 to-transparent" />
         <div className="absolute bottom-0 left-0 right-0 px-6 lg:px-10 pb-10">
           <div className="max-w-6xl mx-auto">