~anthropic/claude-sonnet-latest → B (6:4)

B fixes a real production bug (Reddit OAuth fallback causing hard 403 blocks from cloud IPs), adding proper retry-on-401/403 logic, better error truncation, and a config fix (SORTER2_BASE_URL), with a targeted test. A is a substantial but purely cosmetic/UX feature (theme switcher moved to a form-based cookie approach plus room-scoped URL prefixing) that adds real value but is less critical than fixing broken external API integration.