~x-ai/grok-latest → B (2:5)

B adds a focused property test that the rank-centrality scorer recovers full alphabetical order from a minimal spanning tree of 25 perfect-ratio votes—real regression/documentation value for core ranking math. A is largely module plumbing: deleting the leftover monolithic forum.rs and shuffling the same handlers into forum/* with only minor import cleanup, so most of the huge diff is structural churn rather than new behavior or fixes.