fix: add alert_changed handlers to critical LiveViews

Proactively add catch-all handlers to device index/show pages to
prevent FunctionClauseError when StatusTitleComponent broadcasts
alert changes. These are the most frequently open pages where users
would encounter the crash.

lib/towerops_web/live/device_live/index.ex

@@ -276,6 +276,12 @@ defmodule ToweropsWeb.DeviceLive.Index do
     {:noreply, reload_device_stream(socket)}
   end
 
+  # Handled by StatusTitleComponent in layout - ignore to prevent crashes
+  @impl true
+  def handle_info({:alert_changed, _org_id}, socket) do
+    {:noreply, socket}
+  end
+
   defp tick_interval_ms do
     if Application.get_env(:towerops, :env) == :test, do: :infinity, else: to_timeout(second: 15)
   end

lib/towerops_web/live/device_live/show.ex

@@ -244,6 +244,12 @@ defmodule ToweropsWeb.DeviceLive.Show do
     {:noreply, assign(socket, :show_check_form, false)}
   end
 
+  # Handled by StatusTitleComponent in layout - ignore to prevent crashes
+  @impl true
+  def handle_info({:alert_changed, _org_id}, socket) do
+    {:noreply, socket}
+  end
+
   # Private functions
 
   defp maybe_subscribe_and_schedule_refresh(socket, device_id) do