fix: add migration for rbac ce subject type

Author: hamir-suspect

rbac/ce/priv/repo/migrations/20250723073511_add_subject_type_to_role_assignment.exs

@@ -0,0 +1,24 @@
+defmodule Rbac.Repo.Migrations.AddSubjectTypeToRoleAssignment do
+  use Ecto.Migration
+
+  import Ecto.Query
+
+  def change do
+    alter table(:role_assignment) do
+      add(:subject_type, :string, default: "user")
+    end
+
+    execute(&execute_up/0, &execute_down/0)
+  end
+
+  defp execute_up do
+    repo().update_all(
+      from(r in Rbac.Models.RoleAssignment,
+        where: is_nil(r.subject_type)
+      ),
+      set: [subject_type: "user"]
+    )
+  end
+
+  defp execute_down, do: :ok
+end