Adds three new test rooms to the gauntlet layout at coordinates that tile
correctly with the existing Sprint 11 world. All rooms follow the canonical
entity-registration pattern (StableId 55-62 assigned in spawn order).
- sprint_gauntlet.rs: 32×22 room (StableId 55-57) — Npc_pacing, Npc_guard,
Readable sign. Validates sprint suppression (D-055) at close range.
- eavesdrop_alcove.rs: 24×16 room (StableId 58-60) — two NPC speakers,
corner Readable marker. Validates eavesdrop positioning (D-071).
- confrontation_stage.rs: 32×24 room (StableId 61-62) — Npc_target and
peripheral passer-by NPC. Validates confrontation verb range (D-070).
Updated test_world: mod.rs registers all new rooms, constants.rs adds GAUNTLET
region constant and room spawn points, reset.rs clears all gauntlet rooms.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>