Three-link nav (Chat / Account / Bee) with active-route highlighting,
plus a t4t Gateway home link on the left. Replaces the bespoke header
on the chat page; account and bee gain the same top-of-page nav.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Uses the user's JWT against /v1/models + /v1/chat/completions (the
gateway's /v1 routes already accept JWT — no API key needed for the
in-app chat path; API keys remain for external SDK usage).
Single-turn UX for now, no streaming. Model picker reads /v1/models.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
