openai/gpt-chat-latest → A (3:2)

Side A strengthens Reddit integration by making OAuth mandatory when credentials exist, adding automatic token refresh and retry on 401/403 responses, propagating token acquisition errors instead of silently falling back, and improving diagnostics with truncated error messages plus a regression test. Side B fixes an important multi-user browser voting bug by removing shared sentinel delegates and updating session types and tests, but its scope is more localized compared with A's broader resilience and correctness improvements to external API handling.