feat(npcs): add game-npcs collection for vendors

Developer-gated collection for NPC characters, including the vendor
fields (enabled, priceModifier, sells[]) used by the marketplace to
attribute auto-generated listings to background merchants.

src/collections/game/GameNpcs.ts

@@ -0,0 +1,114 @@
+import { CollectionConfig } from "payload";
+import { isDeveloper } from "@/utils/access-control/isRole";
+
+export const GameNpcs: CollectionConfig = {
+  slug: "game-npcs",
+  admin: {
+    group: "Game",
+    useAsTitle: "name",
+    defaultColumns: ["name", "occupation", "location", "faction", "isGenerated", "isInGame"],
+    listSearchableFields: ["name", "occupation", "bio"],
+    pagination: { defaultLimit: 50 },
+  },
+  access: {
+    read: ({ req }) => !!req.user,
+    create: isDeveloper,
+    update: isDeveloper,
+    delete: isDeveloper,
+  },
+  fields: [
+    {
+      name: "name",
+      type: "text",
+      required: true,
+      admin: {
+        description: "The NPC's name as shown in-game and on the frontend.",
+      },
+    },
+    {
+      name: "occupation",
+      type: "text",
+      admin: {
+        description: "What this NPC does (e.g. 'Weapons Dealer', 'Field Medic').",
+      },
+    },
+    {
+      name: "location",
+      type: "relationship",
+      relationTo: "game-structures",
+      admin: {
+        description: "Where this NPC is stationed in-game.",
+      },
+    },
+    {
+      name: "faction",
+      type: "relationship",
+      relationTo: "factions",
+      admin: {
+        description: "The faction this NPC belongs to, if any.",
+      },
+    },
+    {
+      name: "bio",
+      type: "textarea",
+      admin: {
+        description: "A short background/profile for this NPC.",
+      },
+    },
+    {
+      name: "isGenerated",
+      type: "checkbox",
+      defaultValue: false,
+      admin: {
+        description:
+          "True for NPCs auto-created by the market tick to cover unstocked goods. They are placeholders until included in the game.",
+      },
+    },
+    {
+      name: "isInGame",
+      type: "checkbox",
+      defaultValue: true,
+      admin: {
+        description:
+          "Whether this NPC is officially part of the game. Generated NPCs start off; flip this on to include them.",
+      },
+    },
+    {
+      name: "vendor",
+      label: "Vendor",
+      type: "group",
+      fields: [
+        {
+          name: "enabled",
+          type: "checkbox",
+          defaultValue: false,
+          admin: {
+            description:
+              "Whether this NPC runs a market stall. Auto-generated vendor stock is attributed to them.",
+          },
+        },
+        {
+          name: "priceModifier",
+          type: "number",
+          defaultValue: 1,
+          min: 0.25,
+          max: 5,
+          admin: {
+            description:
+              "Multiplies the auto-generated price for this NPC's stock (1 = base market price).",
+          },
+        },
+        {
+          name: "sells",
+          type: "relationship",
+          relationTo: "assets",
+          hasMany: true,
+          admin: {
+            description:
+              "The goods this NPC sells. The market tick prefers these NPCs when stocking those assets.",
+          },
+        },
+      ],
+    },
+  ],
+};

src/payload.config.ts

@@ -31,6 +31,7 @@ import { GameStructures } from "@/collections/game/GameStructures";
 import { GameHardResources } from "@/collections/game/GameHardResources";
 import { GameEventLogs } from "@/collections/game/GameEventLogs";
 import { GameVehicles } from "@/collections/game/GameVehicles";
+import { GameNpcs } from "@/collections/game/GameNpcs";
 import { Experience } from "@/collections/users/Experience";
 import { BankAccounts } from "@/collections/banking/BankAccounts";
 import { BankTransactions } from "@/collections/banking/BankTransactions";
@@ -78,6 +79,7 @@ export default buildConfig({
     GameHardResources,
     GameStructures,
     GameVehicles,
+    GameNpcs,
     GameEventLogs,
 
     // Users