fix(deps): update nextjs monorepo to v15

Author: renovate[bot]

frontend/package.json

@@ -45,7 +45,7 @@
     "jszip": "^3.10.1",
     "lucide-react": "^0.439.0",
     "multiformats": "^13.2.3",
-    "next": "^14.2.17",
+    "next": "^15.0.0",
     "next-auth": "^4.24.8",
     "nextjs-toploader": "^3.8.16",
     "pino-pretty": "^13.0.0",
@@ -78,7 +78,7 @@
     "@typescript-eslint/eslint-plugin": "^8.13.0",
     "@typescript-eslint/parser": "^8.13.0",
     "eslint": "8.57.1",
-    "eslint-config-next": "14.2.25",
+    "eslint-config-next": "15.3.5",
     "eslint-config-prettier": "^9.1.0",
     "eslint-plugin-jsx-a11y": "^6.10.2",
     "eslint-plugin-prettier": "^5.2.1",