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

Side A performs a real storage-design fix: replaces a capped Deque with an append-only List plus query-time capping, removes the now-unnecessary trim_recent_votes machinery, bumps the schema version, and adds a regression test verifying correct capping behavior. Side B merely deletes a stale duplicate forum.rs that had already been superseded by the forum/ submodule split, resolving a module ambiguity but contributing no new design or behavior beyond cleanup already implied by prior refactors.