Update Next.js version to 15.3.6 (#106)

Author: critesjosh

web-starter/web/nextjs/package.json

@@ -4,7 +4,7 @@
   "dependencies": {
     "@aztec/bb.js": "3.0.0-nightly.20251104",
     "@noir-lang/noir_js": "1.0.0-beta.15",
-    "next": "^15.3.4",
+    "next": "^15.3.6",
     "react": "18.2.0",
     "react-dom": "18.2.0"
   },