chore: sentry and nextjs major bumps (#633)

* chore: remove nextjs-config

* build fix

* sentry update

* nextjs update

* feature flags doc

* update readme

* explicit nextjs env vars + remove feature-unrelated things and obsolete vars from config

* full config removal

* remove force-dynamic from pages

* compile fix

* restore claude-deleted tests

* no sentry backward compat

* better .env.example

* AUTHENTIK_REFRESH_TOKEN_URL not so required

* accommodate auth system to requiredLogin feature

---------

Co-authored-by: Igor Loskutov <igor.loskutoff@gmail.com>

www/package.json

@@ -17,19 +17,19 @@
     "@fortawesome/fontawesome-svg-core": "^6.4.0",
     "@fortawesome/free-solid-svg-icons": "^6.4.0",
     "@fortawesome/react-fontawesome": "^0.2.0",
-    "@sentry/nextjs": "^7.77.0",
+    "@sentry/nextjs": "^10.11.0",
     "@tanstack/react-query": "^5.85.9",
     "@types/ioredis": "^5.0.0",
     "@whereby.com/browser-sdk": "^3.3.4",
     "autoprefixer": "10.4.20",
     "axios": "^1.8.2",
     "eslint": "^9.33.0",
-    "eslint-config-next": "^14.2.31",
+    "eslint-config-next": "^15.5.3",
     "fontawesome": "^5.6.3",
     "ioredis": "^5.7.0",
     "jest-worker": "^29.6.2",
     "lucide-react": "^0.525.0",
-    "next": "^14.2.30",
+    "next": "^15.5.3",
     "next-auth": "^4.24.7",
     "next-themes": "^0.4.6",
     "nuqs": "^2.4.3",