- run_tests.js discovers and runs each *_test.js in its own worker process
(--jobs N to cap the pool, --file <name> for a single suite)
- GameState caches the deterministic terrain, city sites and road network by
(seed, mapConfig, civ count), rebuilding only the mutable per-game state
- the snapshot ships mapConfig and the client rebuilds terrain from it, so the
DOM tests can use the small map fixture and a non-default config renders right
- shortestPaths can stop once every target city is settled