upgrade to next js 15.2.6

Author: MatiasSinisalo

package-lock.json

@@ -17,7 +17,7 @@
     "framer-motion": "^12.5.0",
     "gray-matter": "^4.0.3",
     "mui-markdown": "^1.2.5",
-    "next": "^15.2.3",
+    "next": "^15.2.6",
     "raw-loader": "^4.0.2",
     "react": "^19.0.0",
     "react-dom": "^19.0.0",