Implement currency, shops, and enhanced NPC interaction system

world/lawold/npcs/breda.toml

@@ -3,3 +3,13 @@ description = "Breda is haughty in bearing, with thin auburn hair and narrow blu
 room = "lawold:well_market_trade_stalls"
 race = "race:human"
 base_attitude = "aggressive"
+
+[dialogue]
+greeting = "What do you want? I'm busy. Unless you have some teeth to sell?"
+keywords = { teeth = "I buy monster teeth. One silver each. No questions asked.", tools = "My tools aren't for sale, but I have some spares if you have the coin." }
+
+[shop]
+buys = ["junk", "teeth", "tool"]
+sells = ["town:small_hammer", "town:chisel"]
+markup = 1.2
+markdown = 0.5

world/town/objects/chisel.toml

@@ -0,0 +1,7 @@
+name = "Chisel"
+description = "A sharp steel chisel, used for fine woodwork or stone carving."
+kind = "tool"
+takeable = true
+value_gold = 0
+value_silver = 3
+value_copper = 50

world/town/objects/small_hammer.toml

@@ -0,0 +1,7 @@
+name = "Small Hammer"
+description = "A sturdy iron hammer with a wooden handle, suitable for small repairs or light construction."
+kind = "tool"
+takeable = true
+value_gold = 0
+value_silver = 5
+value_copper = 0