Update migrations

priv/repo/migrations/20250615131158_create_users.exs

@@ -0,0 +1,20 @@
+defmodule Nulla.Repo.Migrations.CreateUsers do
+  use Ecto.Migration
+
+  def change do
+    create table(:users, primary_key: false) do
+      add :id, :bigint, primary_key: true
+      add :email, :string
+      add :password, :string
+      add :privateKeyPem, :string
+      add :last_active_at, :utc_datetime
+
+      add :actor_id, references(:actors, column: :id, type: :bigint, on_delete: :delete_all),
+        null: false
+
+      timestamps(type: :utc_datetime)
+    end
+
+    create unique_index(:users, [:actor_id])
+  end
+end