openai/gpt-5.3-chat → B (9:1)

Commit B introduces a substantial new capability: an extensible external URL system with a full GitHub resolver, backend ingestion pipeline, UI controls, normalization logic, and extensive tests (including browser automation). It touches many core areas (state, API, DSL, HTML, URL identity, and async workers) and adds meaningful product functionality. Commit A is a focused UI/logic fix for vote highlighting with some styling and tests—useful but comparatively small in scope and impact.