disconnected (1008): Invalid or missing token when using Cloudflare Access with custom domain

## Problem
When using Cloudflare Access with a custom domain, the `?token=` query parameter
is stripped during the Access redirect, causing a 1008 "Invalid or missing token"
error in the Chat UI.

## Steps to reproduce
1. Deploy moltworker with Cloudflare Access enabled
2. Set MOLTBOT_GATEWAY_TOKEN as a secret
3. Configure a custom domain (e.g. moltbot.example.com) with Cloudflare Access
4. Visit https://moltbot.example.com/?token=YOUR_TOKEN
5. After Cloudflare Access authentication, the token is stripped from the URL
6. Chat UI shows: disconnected (1008): Invalid or missing token

## Expected behavior
The token should be preserved after the Cloudflare Access redirect,
or the UI should store the token in sessionStorage/localStorage before the redirect.

## Environment
- Custom domain with Cloudflare Access (Azure AD / Entra ID)
- Workers Paid plan
- Latest version of moltworker (forked from cloudflare/moltworker)

## Workaround
None found. The /_admin/ page works correctly with Cloudflare Access.