chore: update next.js to 15.5.18

Bump next, @next/third-parties, and eslint-config-next to the latest
15.x semver-compatible release.

https://claude.ai/code/session_01KutsEUcXaUPQaDAfjmLhur

Author: claude

package.json

@@ -22,7 +22,7 @@
     "@dnd-kit/utilities": "^3.2.2",
     "@hookform/resolvers": "^3.10.0",
     "@next-auth/prisma-adapter": "^1.0.7",
-    "@next/third-parties": "^15.5.7",
+    "@next/third-parties": "^15.5.18",
     "@planetscale/database": "^1.19.0",
     "@prisma/adapter-planetscale": "^6.19.0",
     "@prisma/client": "6.3.0",
@@ -101,7 +101,7 @@
     "micro": "^10.0.1",
     "motion": "^12.23.25",
     "near-api-js": "^5.1.1",
-    "next": "^15.5.9",
+    "next": "^15.5.18",
     "next-auth": "^4.24.13",
     "next-axiom": "^0.18.1",
     "next-pwa": "^5.6.0",
@@ -161,7 +161,7 @@
     "autoprefixer": "^10.4.22",
     "cross-env": "^7.0.3",
     "eslint": "^8.57.1",
-    "eslint-config-next": "^15.5.7",
+    "eslint-config-next": "^15.5.18",
     "eslint-config-prettier": "^9.1.2",
     "eslint-plugin-react": "^7.37.5",
     "eslint-plugin-react-hooks": "^5.2.0",