fix: resolve multiple runtime and build issues

- Fix network binding to allow external access (0.0.0.0)
- Upgrade to Node.js 20.x for Next.js 16 compatibility
- Fix next-auth v4 configuration and session handling
- Add Steam client secret for Steam OAuth provider
- Fix Prisma schema unique constraint syntax
- Fix database creation script for automated deployment
- Fix game search API to use new IStoreService endpoint
- Fix session auth in API routes for Steam linking
- Add TypeScript types for next-auth session

prisma/schema.prisma

@@ -67,6 +67,6 @@ model Vote {
   user   User   @relation(fields: [userId], references: [id])
   review Review @relation(fields: [reviewId], references: [id])
 
-  @@unique([userId, reviewId]) @map("user_review_unique")
+  @@unique([userId, reviewId], name: "user_review_unique")
   @@map("votes")
 }