feat(infrastructure): add FluentMigrator migrations for database schema

src/IncidentOps.Infrastructure/Migrations/Migration0002_RefreshTokens.cs

@@ -0,0 +1,28 @@
+using FluentMigrator;
+
+namespace IncidentOps.Infrastructure.Migrations;
+
+[Migration(2)]
+public class Migration0002_RefreshTokens : Migration
+{
+    public override void Up()
+    {
+        Create.Table("refresh_tokens")
+            .WithColumn("id").AsGuid().PrimaryKey()
+            .WithColumn("user_id").AsGuid().NotNullable().ForeignKey("users", "id").OnDelete(System.Data.Rule.Cascade)
+            .WithColumn("token_hash").AsString(255).NotNullable().Unique()
+            .WithColumn("active_org_id").AsGuid().NotNullable().ForeignKey("orgs", "id").OnDelete(System.Data.Rule.Cascade)
+            .WithColumn("expires_at").AsDateTime().NotNullable()
+            .WithColumn("revoked_at").AsDateTime().Nullable()
+            .WithColumn("created_at").AsDateTime().NotNullable().WithDefault(SystemMethods.CurrentUTCDateTime);
+
+        Create.Index("ix_refresh_tokens_user")
+            .OnTable("refresh_tokens")
+            .OnColumn("user_id").Ascending();
+    }
+
+    public override void Down()
+    {
+        Delete.Table("refresh_tokens");
+    }
+}