feat: centralized constants and enums for project-wide use

src/modules/trade/trade.service.ts

@@ -4,6 +4,7 @@ import { inventoryService } from "@/modules/inventory/inventory.service";
 import { itemTransactions } from "@/db/schema";
 import { withTransaction } from "@/lib/db";
 import type { Transaction } from "@/lib/types";
+import { TransactionType, ItemTransactionType } from "@/lib/constants";
 
 // Module-level session storage
 const sessions = new Map<string, TradeSession>();
@@ -25,7 +26,7 @@ const processTransfer = async (tx: Transaction, from: TradeParticipant, to: Trad
         await economyService.modifyUserBalance(
             from.id,
             -from.offer.money,
-            'TRADE_OUT',
+            TransactionType.TRADE_OUT,
             `Trade with ${to.username} (Thread: ${threadId})`,
             to.id,
             tx
@@ -33,7 +34,7 @@ const processTransfer = async (tx: Transaction, from: TradeParticipant, to: Trad
         await economyService.modifyUserBalance(
             to.id,
             from.offer.money,
-            'TRADE_IN',
+            TransactionType.TRADE_IN,
             `Trade with ${from.username} (Thread: ${threadId})`,
             from.id,
             tx
@@ -54,7 +55,7 @@ const processTransfer = async (tx: Transaction, from: TradeParticipant, to: Trad
             relatedUserId: BigInt(to.id),
             itemId: item.id,
             quantity: -item.quantity,
-            type: 'TRADE_OUT',
+            type: ItemTransactionType.TRADE_OUT,
             description: `Traded to ${to.username}`,
         });
 
@@ -64,7 +65,7 @@ const processTransfer = async (tx: Transaction, from: TradeParticipant, to: Trad
             relatedUserId: BigInt(from.id),
             itemId: item.id,
             quantity: item.quantity,
-            type: 'TRADE_IN',
+            type: ItemTransactionType.TRADE_IN,
             description: `Received from ${from.username}`,
         });
     }