openai/gpt-chat-latest → A (5:2)

Side A fixes a substantive concurrency bug by ensuring `tokio::sync::RwLock` read guards are dropped before later `read().await`/`write().await` calls in `RoomCreate` and `RoomGrant`, preventing self-deadlocks from non-reentrant lock usage. It also adds an integration test for private room creation and improves test robustness, whereas Side B is primarily a feature/UI enhancement for the vote-compare page (fullscreen layout, preview morphing, sorting/display changes) with accompanying tests rather than a core correctness fix.