feat: Initialize database and restructure application source code.

src/db/schema.ts

@@ -0,0 +1,19 @@
+import { pgTable, integer, text, timestamp, serial } from "drizzle-orm/pg-core";
+
+export const users = pgTable("users", {
+    userId: text("user_id").primaryKey().notNull(),
+    balance: integer("balance").notNull().default(0),
+    lastDaily: timestamp("last_daily"),
+    dailyStreak: integer("daily_streak").notNull().default(0),
+    createdAt: timestamp("created_at").defaultNow(),
+});
+
+export const transactions = pgTable("transactions", {
+    transactionId: serial("transaction_id").primaryKey().notNull(),
+    fromUserId: text("from_user_id").references(() => users.userId),
+    toUserId: text("to_user_id").references(() => users.userId),
+    amount: integer("amount").notNull(),
+    occuredAt: timestamp("occured_at").defaultNow(),
+    type: text("type").notNull(),
+    description: text("description"),
+});