Fix Next.js security vulnerability by upgrading to v15.0.8+

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

packages/adapters/nextjs/package.json

@@ -9,15 +9,15 @@
   },
   "peerDependencies": {
     "@objectstack/runtime": "workspace:*",
-    "next": "^14.0.0",
+    "next": "^15.0.8",
     "react": "^19.2.4",
-    "react-dom": "^18.3.1"
+    "react-dom": "^19.2.4"
   },
   "devDependencies": {
     "@objectstack/runtime": "workspace:*",
-    "next": "^14.0.0",
+    "next": "^15.0.8",
     "react": "^19.2.4",
-    "react-dom": "^18.3.1",
+    "react-dom": "^19.2.4",
     "typescript": "^5.0.0"
   }
 }