Add email_activation_codes table (#3426)

* Add email_activation_codes table

* Change code column in migration to string

priv/repo/migrations/20231011101825_add_email_activation_codes.exs

@@ -0,0 +1,14 @@
+defmodule Plausible.Repo.Migrations.AddEmailActivationCodes do
+  use Ecto.Migration
+
+  def change do
+    create table(:email_activation_codes) do
+      add :code, :text, null: false
+      add :user_id, references(:users, on_delete: :delete_all), null: false
+
+      add :issued_at, :naive_datetime, null: false
+    end
+
+    create unique_index(:email_activation_codes, :user_id)
+  end
+end