The NetworkFirst route for /api/* was intercepting the OIDC callback
(/api/auth/oauth2/callback/authentik?code=...), returning a cached
index.html instead of forwarding to the API server.
Added navigateFallbackDenylist regex to exclude the callback path
from service worker navigation handling, allowing the callback request
to reach the API server normally.
Fixes GRO-472.
Co-Authored-By: Paperclip <noreply@paperclip.ing>