wire spec-driven auth: remove VITE_AUTH_BASE_URL, reorder providers

- main.jsx: remove VITE_AUTH_BASE_URL env var; add AppContent that
  reads authConfig from useAppContext() and passes to AuthProvider;
  reorder: AppProvider -> AuthProvider -> BrowserRouter
- sync react-openapi: AuthConfig type, extractAuthConfig, loading fix
- sync react-auth: authConfig prop, config-driven paths, server logout

react-auth/index.ts

@@ -1,4 +1,5 @@
 export { AuthProvider, useAuth } from "./contexts";
+export type { AuthServerConfig } from "./contexts";
 export { createApiClient } from "./axios";
 export { AuthPage } from "./AuthPage";
 export { ProfileCreate } from "./ProfileCreate";