chore(deps): update nextjs monorepo to ^16.2.9 (#1743)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.templates/template-next/package.json

@@ -9,7 +9,7 @@
     "start": "next start"
   },
   "dependencies": {
-    "next": "^16.2.8",
+    "next": "^16.2.9",
     "react": "^19.2.7",
     "react-dom": "^19.2.7"
   },

next-full/package.json

@@ -11,7 +11,7 @@
   "dependencies": {
     "beautiful-mermaid": "^1.1.3",
     "katex": "^0.17.0",
-    "next": "^16.2.8",
+    "next": "^16.2.9",
     "prosekit": "^0.21.4",
     "react": "^19.2.7",
     "react-dom": "^19.2.7"