Salvage Rush runs no NPCs: a world definition can name its own (npcSpawns, [] for none), and the arena did get the procedural world's townsfolk, warden and Rustjaw thugs (#126)

ddiff --git a/CHANGELOG.md b/CHANGELOG.md
iindex 2458fe1..212c671 100644
---- a/CHANGELOG.md
++++ b/CHANGELOG.md
@@@ -8,6 +8,10 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
  
  ### Fixed
  
++- **Townsfolk in the Salvage Rush arena.** The 90-second scrap round ran the content's seven NPC spawns, laid out for
++  the procedural world: townsfolk and a warden wandered inside the arena and Rustjaw thugs stood just past its edge.
++  A world definition can now name its own NPCs (`npcSpawns`; `[]` is none), and the arena has none. A map's own NPCs
++  still win.
  - **Touch play's HUD was buried under the controls.** On a phone, the stick (bottom left) and the button grid (bottom
    right) covered the first-steps panel, and the HP, food, water and stamina bars sat on the hotbar. While the touch
    controls show:
ddiff --git a/packages/content/src/defs/npcs.ts b/packages/content/src/defs/npcs.ts
iindex 618bc37..f6c120e 100644
---- a/packages/content/src/defs/npcs.ts
++++ b/packages/content/src/defs/npcs.ts
@@@ -124,6 +124,7 @@ export interface NpcSpawn {
  export function npcSpawnsFor(world?: WorldDef): NpcSpawn[] {
    const mapped = getMapOverride(world)?.npcs ?? []
    if (mapped.length) return mapped.map((n) => ({ archetype: n.npc, pos: n.pos }))
++  if (world?.npcSpawns) return world.npcSpawns
    return NPC_SPAWNS
  }
  
ddiff --git a/packages/content/src/mapFileV2.test.ts b/packages/content/src/mapFileV2.test.ts
iindex 4c7f72d..3c2d4a4 100644
---- a/packages/content/src/mapFileV2.test.ts
++++ b/packages/content/src/mapFileV2.test.ts
@@@ -12,6 +12,8 @@ import {
  } from './mapFileV2.js'
  import { NPC_SPAWNS, npcSpawnsFor } from './defs/npcs.js'
  import { setMapOverride } from './terrain.js'
++import { SALVAGE_RUSH_PACK } from './packs/salvageRush.js'
++import type { WorldDef } from './schema/world.js'
  
  const SUB = 8
  
@@@ -473,6 +475,19 @@ describe('map-authored NPCs', () => {
      expect(npcSpawnsFor()).toBe(NPC_SPAWNS)
    })
  
++  it("a world with its own spawns (none, in Salvage Rush's arena) is not given the content's", () => {
++    const arena = SALVAGE_RUSH_PACK.map as WorldDef
++    expect(arena.npcSpawns).toEqual([])
++    expect(npcSpawnsFor(arena)).toEqual([])
++    // A map that places NPCs still wins.
++    setMapOverride({ terrains: [], npcs: [{ id: 'n', npc: 'dust_hare', pos: [1, 0, 1] }] })
++    try {
++      expect(npcSpawnsFor(arena)).toEqual([{ archetype: 'dust_hare', pos: [1, 0, 1] }])
++    } finally {
++      setMapOverride(null)
++    }
++  })
++
    it('an NPC id may not repeat another object id', () => {
      const map: MapFileV2 = {
        ...emptyMapV2(),
ddiff --git a/packages/content/src/packs/salvageRush.ts b/packages/content/src/packs/salvageRush.ts
iindex b83712e..8bba32d 100644
---- a/packages/content/src/packs/salvageRush.ts
++++ b/packages/content/src/packs/salvageRush.ts
@@@ -17,6 +17,9 @@ export const SALVAGE_RUSH_PACK: ContentPackV2 = {
      ],
      resourceNodes: [],
      initialProps: [],
++    // A 90-second scrap round: no NPCs. The content's spawns put townsfolk and a warden inside the arena and Rustjaw
++    // thugs just past its edge.
++    npcSpawns: [],
      zones: [
        {
          id: 'arena',
ddiff --git a/packages/content/src/schema/world.ts b/packages/content/src/schema/world.ts
iindex 954fffe..c8446aa 100644
---- a/packages/content/src/schema/world.ts
++++ b/packages/content/src/schema/world.ts
@@@ -155,6 +155,11 @@ export const WorldDefSchema = z.object({
    resourceNodes: z.array(ResourceNodeSpawnSchema),
    initialProps: z.array(PropSpawnSchema),
    zones: z.array(ZoneDefSchema),
++  /**
++   * The world's own NPCs, when it has an opinion: `[]` for none (a timed arena), else archetypes and ground
++   * positions. Absent, it gets the content's NPC_SPAWNS. A map's own NPCs win over either (npcSpawnsFor).
++   */
++  npcSpawns: z.array(z.object({ archetype: z.string(), pos: vec3 })).optional(),
  })
  
  export type WorldDef = z.infer<typeof WorldDefSchema>