~anthropic/claude-sonnet-latest → B (85:15)

Side B ships a substantial, working feature: GitHub OAuth login, session management, pseudonym claiming, trust-weight identity events, projection/storage schema updates, route wiring, JS/UI changes, and new integration tests, plus it removes an in-tree crate in favor of a git dependency (real infra cleanup). Side A is purely a planning document plus a thin unfinished RouteContext wrapper that just delegates to existing ThreadNav methods with no call-site migration, providing far less concrete lasting value than the shipped auth system in B.