feat(chat): chat name is unique

lib/slax/chat/room.ex

@@ -19,5 +19,6 @@ defmodule Slax.Chat.Room do
       message: "can only contain lowercase letters, numbers, and dashes"
     )
     |> validate_length(:topic, max: 200)
+    |> unique_constraint(:name)
   end
 end

priv/repo/migrations/20241021233716_alter_rooms_add_unique_on_name.exs

@@ -0,0 +1,7 @@
+defmodule Slax.Repo.Migrations.AlterRoomsAddUniqueOnName do
+  use Ecto.Migration
+
+  def change do
+    create unique_index(:rooms, :name)
+  end
+end