User defined routes can override /oauth/callback and break OAuth flow

[infomiho]

Context: https://ptb.discord.com/channels/686873244791210014/1238173111363305574/1239325290824732673

If users define a wildcard route (to serve as a error page for missing routes) they will override the OAuth callback because user routes come before Wasp defined routes.

We should make sure Wasp defined routes are before in the router.tsx.