✨Feature: implement town market functionality with treasure selling and stashing

src/types/state.ts

@@ -215,6 +215,7 @@ export type RunState = {
   dungeon: DungeonState;
   adventurerSnapshot: AdventurerState;
   activeCombat?: CombatState;
+  townState: TownState;
   defeatedCreatureIds: string[];
   xpGained: number;
   goldGained: number;