Refactor. Add data layer

BudgetApp.Data/Migrations/AddIsPaidToTransaction.cs

@@ -0,0 +1,28 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace BudgetApp.Data.Migrations;
+
+/// <inheritdoc />
+public partial class AddIsPaidToTransaction : Migration
+{
+    /// <inheritdoc />
+    protected override void Up(MigrationBuilder migrationBuilder)
+    {
+        migrationBuilder.AddColumn<bool>(
+            name: "IsPaid",
+            table: "Transactions",
+            type: "INTEGER",
+            nullable: false,
+            defaultValue: false);
+    }
+
+    /// <inheritdoc />
+    protected override void Down(MigrationBuilder migrationBuilder)
+    {
+        migrationBuilder.DropColumn(
+            name: "IsPaid",
+            table: "Transactions");
+    }
+}