openai/gpt-chat-latest → A (3:2)

Side A centralizes base URL generation into a shared utility, replaces multiple hardcoded host/environment checks across OAuth/login integrations, uses the current browser origin on the frontend, and updates deployment to run from the staging branch. Side B introduces cleaner browse URLs and removes the theme system, but much of the patch is feature/refactoring churn and deletion, whereas Side A directly fixes incorrect redirect behavior for custom hosts across several authentication flows.