feat: switch to phoenix liveview

Co-authored-by: Copilot <copilot@github.com>

lib/bds/desktop/error_html.ex

@@ -0,0 +1,9 @@
+defmodule BDS.Desktop.ErrorHTML do
+  @moduledoc false
+
+  use Phoenix.Component
+
+  def render(_template, _assigns) do
+    "not found"
+  end
+end