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

Commit A delivers substantial new functionality: cookie-based web sessions, a login/logout flow, private room routing (/r/:short/:slug/...), room-scoped thread views with ACL checks, and a full web posting handler — real, functional feature additions. Commit B is a refactor that consolidates existing /post endpoints into a single /ui RPC dispatcher, which is reasonable cleanup but net-negative in some spots (e.g., includes stray irrelevant plan2.md-adjacent content isn't here, but B's diff shows leftover TODOs and duplicate JSON-building boilerplate), making it useful but comparatively lower-impact than A's feature buildout.