feat: theme dashboard charts and expose admin UI on HF Spaces

feat: add usage tracking with live throughput rates and analytics dashboard

feat: surface saved endpoint models and revamp the admin UI

fix: cache-bust admin UI and show the running version

feat: admin dedicated pages, pool key management, keypool quotas (#1350)

Add ChatGPT OAuth as an OpenAI Codex provider (#1279)

Add searchable model selection to the Admin UI (#1121)

Establish single-owner runtime with stream-safe provider hot swaps (#1036)

Move runtime packages under src namespace (#1029)