feat: add SteamGridDB proxy API for non-Steam game images

app/api/[[...slugs]]/route.ts

@@ -24,6 +24,7 @@ import { searchUnifiedRoutes } from "@/lib/api/search-unified"
 import { gameStubRoutes } from "@/lib/api/game-stub"
 import { gameStatsRoutes } from "@/lib/api/game-stats"
 import { gamesListingRoutes } from "@/lib/api/games-listing"
+import { steamgridProxyRoutes } from "@/lib/api/steamgrid-proxy"
 
 const betterAuth = new Elysia({ name: "better-auth" })
   .mount(auth.handler)
@@ -84,6 +85,8 @@ export const app = new Elysia({ prefix: "/api" })
   .use(searchUnifiedRoutes)
   // Game stub creation
   .use(gameStubRoutes)
+  // SteamGridDB proxy
+  .use(steamgridProxyRoutes)
   // Game stats aggregation
   .use(gameStatsRoutes)
   // Saved games