fix: resolve Next.js 16 build errors

- Extract Elysia app from route.ts into lib/api/app.ts to avoid
  Next.js 16 invalid export validation ('app' is not a valid route
  export field)
- Remove runtime='nodejs' from opengraph-image.tsx (invalid segment
  config in Next.js 16)
- Replace computed revalidate expression in sitemap.ts with literal
  (Next.js cannot statically evaluate BinaryExpression for segment
  configs)
- Update eden.ts imports to match new app.ts location

app/devices/[slug]/opengraph-image.tsx

@@ -3,7 +3,6 @@ import { db } from "@/lib/db/index"
 import { hardware, performanceEntries, gameVersions, games } from "@/lib/db/schema"
 import { eq, and, sql } from "drizzle-orm"
 
-export const runtime = "nodejs"
 export const dynamic = "force-dynamic"
 export const alt = "Device benchmarks on DeckyVault"
 export const size = { width: 1200, height: 630 }