Dungeon venue: grid-first traversable dungeon with cast, loot and encounters

New VenueGenerator 'dungeon' archetype. The floor plan is generated first
on a 44x44 grid (rejection-sampled rooms, Kruskal MST + loop edges,
L-shaped corridors, BFS-verified connectivity); walls are merged runs
built exactly where open meets solid, so the shell has no holes, and
the walk route is a closed travelling tour through every room.

The camera either walks first-person (hero hidden to avoid clipping) or
plants on a per-room watch cell with line-of-sight to the route and
tracks the actor. Enemies (walker/structure/swarm ActorSpecs from the
track's own summary) lurk, stand sentry, dart and drift; loot caches
pause the analytic odometer, which can hold or advance but never retreat.

Includes dungeon-debug.html (2D map + timeline stills), 14 map tests
plus facade camera tests, and the portcullis-holds-for-the-whole-party
regression test.

flow-state/tools/new-venue.js

@@ -9,7 +9,7 @@ import { fileURLToPath } from 'url';
 const root = join(dirname(fileURLToPath(import.meta.url)), '..');
 const VENUES = join(root, 'src/venues');
 const REGISTRY = join(root, 'src/venues/registry.js');
-const ARCHETYPES = ['chamber','stage','ride'];
+const ARCHETYPES = ['chamber','stage','ride','dungeon'];
 const args = process.argv.slice(2);
 const flags = new Map(args.filter(a=>a.startsWith('--')).map(a=>{ const [k,v]=a.replace(/^--/,'').split('='); return [k, v===undefined?true:v]; }));
 const name = args.find(a=>!a.startsWith('--'));