server.ts calls OidcService.initialize() inside the Express app setup, but
oidcRoutes.ts was calling OidcService.callback() at module-load time — before
initialize() had been called. This caused the server to crash immediately on
startup with "OidcService not initialized. Call initialize() first."

The fix wraps the callback in a lazy arrow function so it is only resolved
when the route handler fires, by which point initialize() has already run.
tsc --noEmit clean; server starts successfully after this change.
Co-authored-by: Cursor <cursoragent@cursor.com>