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.
Dejvino