feat: Introduce new modules for class, inventory, leveling, and quests with expanded schema, refactor user service, and add verification scripts.

src/modules/user/user.service.ts

@@ -0,0 +1,44 @@
+import { users } from "@/db/schema";
+import { eq, sql } from "drizzle-orm";
+import { DrizzleClient } from "@/lib/DrizzleClient";
+
+export const userService = {
+    getUserById: async (id: string) => {
+        const user = await DrizzleClient.query.users.findFirst({
+            where: eq(users.id, BigInt(id)),
+            with: { class: true }
+        });
+        return user;
+    },
+    getUserByUsername: async (username: string) => {
+        const user = await DrizzleClient.query.users.findFirst({ where: eq(users.username, username) });
+        return user;
+    },
+    createUser: async (id: string | bigint, username: string, classId?: bigint, tx?: any) => {
+        const execute = async (txFn: any) => {
+            const [user] = await txFn.insert(users).values({
+                id: BigInt(id),
+                username,
+                classId,
+            }).returning();
+            return user;
+        };
+        return tx ? await execute(tx) : await DrizzleClient.transaction(execute);
+    },
+    updateUser: async (id: string, data: Partial<typeof users.$inferInsert>, tx?: any) => {
+        const execute = async (txFn: any) => {
+            const [user] = await txFn.update(users)
+                .set(data)
+                .where(eq(users.id, BigInt(id)))
+                .returning();
+            return user;
+        };
+        return tx ? await execute(tx) : await DrizzleClient.transaction(execute);
+    },
+    deleteUser: async (id: string, tx?: any) => {
+        const execute = async (txFn: any) => {
+            await txFn.delete(users).where(eq(users.id, BigInt(id)));
+        };
+        return tx ? await execute(tx) : await DrizzleClient.transaction(execute);
+    },
+};