feat(chat): chat name is unique

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