## Bug Description

When the user's authentication session expires while navigating the LiteLLM UI, the frontend does not redirect to the login page. Instead, the current page freezes and all components start displaying 401 (Unauthorized) errors.

## Steps to Reproduce

1. Log in to the LiteLLM UI 2. Leave the session idle long enough for the authentication to expire (or let the token expire) 3. Interact with the page or wait for components to refresh

## Expected Behavior

When the authentication expires, the UI should automatically redirect the user to the login page so they can re-authenticate.

## Actual Behavior

- The page freezes and becomes unresponsive - No redirect to the login page is triggered - The user is stuck on a broken page with no way to re-authenticate without manually navigating to the login URL

## Impact

This leads to a poor user experience. Users are left on a non-functional page with error messages they may not understand, with no clear path to re-authenticate.

## Environment

- LiteLLM UI (browser-based admin interface)

## Suggested Fix

The frontend should intercept 401 responses globally and redirect the user to the login page when the session has exp…