openai/gpt-5.3-chat → A (8:2)

A removes a 1400+ line monolithic `forum.rs`, resolves module ambiguity, and introduces a structured `forum/` module with separated concerns (feed, paginator, views, etc.), improving maintainability. B is a one-line change swapping a disabled `<span>` for an `<a>` in the paginator, a minor UI consistency tweak with limited impact.