jev-arena

# Jev Arena design Jev Arena shows a live grid and a "Jev's brain" panel: Jev (TypeSafe's System One model) chooses a move every `arena.speed` ms, and the viewer streams the probability distribution and confidence for `up / down / left / right / wait`. ## The loop 1. Update `arena.json`. The viewer watches it and adapts live — no restart, no second server. 2. `node "$JEV_DSH/toolchain/check.mjs"` verifies the workspace's `arena.json` is a valid, playable world, and reports the current verdict / status. Run it before you call a world done. 3. Watch Jev play. When the layout changes, that's the moment to look: does Jev's confidence dip and recover? Is the route interesting? ## Reading Jev The viewer shows, per action, a probability bar and the chosen action highlighted. `confidence` is a 0..1 concentration of the distribution. A confident Jev puts most mass on one move; a confused Jev spreads it. Good arenas produce both states. ## Verifying a world `node "$JEV_DSH/toolchain/check.mjs"` returns non-zero when `arena.json` is invalid (missing fields, out-of-bounds, goal covered by a wall). It does not replace watching Jev actually play. Always confirm Jev can reach the goal by stepping or running it. ## Driving Jev yourself `toolchain/jev.mjs` exports a small client. Example (from the workspace): ```bash node --input-type=module -e ' import { evaluate, jev } from "$JEV_DSH/toolchain/jev.mjs"; import { readFileSync } from "node:fs"; const world = JSON.parse(readFil...