chore(dev): serve the portal on 3000 for the Fayda redirect

The Fayda redirect URI registered for local testing is
http://localhost:3000/callback, matched exactly by the provider, so the portal
has to be the thing listening there. Its dev and preview servers move from 4200
to 3000 and the API moves to 3001.

Every hardcoded fallback to http://localhost:3000/api follows — six copies of
the same default across libs/api, libs/auth, the portal and the backoffice —
otherwise a developer without a .env would have had the app calling itself.

e2e is unaffected: it binds its own ports (3011/4302/4303) explicitly.

libs/auth/src/lib/components/AuthBootstrap.tsx

@@ -8,7 +8,7 @@ import type { AuthUser } from '../types/auth.types';
 
 const BASE_API_URL =
   (import.meta as { env?: Record<string, string> }).env?.['VITE_BASE_API_URL'] ??
-  'http://localhost:3000/api';
+  'http://localhost:3001/api';
 
 /**
  * Restores the signed-in session before the router renders.