The portal store merged events from the API with localStorage events
without ever pruning stale entries. When /auth/me returned empty
portal_events (e.g. after a person's user_id was cleared), localStorage
events persisted, causing "registratie niet ophalen" when /portal/me
correctly returned 404.
Now when /auth/me succeeds, API data is the source of truth — stored
events not confirmed by the API are dropped. localStorage fallback is
only used when the API call fails (network error).
Also adds an end-to-end test covering the full register → approve →
portal/me flow including festival hierarchy.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>