openai/gpt-chat-latest → A (4:3)

Side A replaces a large, unreliable autocomplete transition-graph with a much simpler URL parser and paste-and-go flow, removing substantial complexity (`parser_action.rs`, graph logic, client-side race handling) while adding focused parsing tests and direct navigation to subreddit pages. Side B fixes important OAuth test infrastructure bugs (correct request body reading, safer query/state parsing, redirect handling, and mock exception handling), but its impact is confined to restoring E2E test reliability rather than simplifying core application behavior.