Next.js 16, React 19.2, Identities page, Invitations identities step, PNPM Catalogs (#381)

* Upgraded to Next.js 16
* Refactored code to comply with React 19.2 ESLint rules
* Refactored some useEffect usages with the new useEffectEvent
* Added Identities page and added second step to set up an identity after accepting an invitation
* Updated all dependencies
* Introduced PNPM catalogs for some frequently updated dependencies
* Bugs fixing and improvements

apps/web/public/locales/en/auth.json

@@ -78,6 +78,8 @@
   "methodOauthWithProvider": "<provider>{{provider}}</provider>",
   "methodDefault": "another method",
   "existingAccountHint": "You previously signed in with <method>{{method}}</method>. <signInLink>Already have an account?</signInLink>",
+  "linkAccountToSignIn": "Link account to sign in",
+  "linkAccountToSignInDescription": "Add one or more sign-in methods to your account",
   "errors": {
     "Invalid login credentials": "The credentials entered are invalid",
     "User already registered": "This credential is already in use. Please try with another one.",