~x-ai/grok-latest → A (3:1)

A adds a concrete, phased storage/architecture plan (JSONL as source of truth, durable RocksDB projections, RAM bounded to hot scopes, write/read/startup paths) that defines lasting product direction under the 256MB constraint. B only improves local DX (cargo-watch fixture, persistent fixture-data/, preferred port) plus a small room-page markup trim—useful iteration friction reduction, but not fundamental system design.