fix/traffic-graph-monitored-nil (#127)

Reviewed-on: graham/towerops-web#127

lib/towerops_web/live/device_live/show.ex

@@ -233,6 +233,13 @@ defmodule ToweropsWeb.DeviceLive.Show do
     end
   end
 
+  @impl true
+  def handle_info({:alert_changed, _organization_id}, socket) do
+    # Alert changed in this organization - we don't show alerts on device page
+    # so just ignore this message
+    {:noreply, socket}
+  end
+
   @impl true
   def handle_info({FormComponent, {:check_created, _check}}, socket) do
     {:noreply,
@@ -1204,10 +1211,10 @@ defmodule ToweropsWeb.DeviceLive.Show do
 
   # Calculate BPS per interface first, then aggregate by timestamp
   # This avoids issues with misaligned timestamps between interfaces
-  # Only processes monitored interfaces to match actual traffic being tracked
+  # Only processes monitored interfaces (nil treated as true for backwards compatibility)
   defp aggregate_interface_traffic_stats(interfaces, since) do
     interfaces
-    |> Enum.filter(& &1.monitored)
+    |> Enum.filter(&(&1.monitored != false))
     |> Enum.flat_map(fn interface ->
       interface.id
       |> Snmp.get_interface_stats(since: since, limit: 1000)
@@ -1407,9 +1414,10 @@ defmodule ToweropsWeb.DeviceLive.Show do
   # Sums capacity of active interfaces at each timestamp
   defp calculate_interface_capacity_data(all_stats, device) do
     # Build a map of interface_id -> {rx_capacity, tx_capacity} for quick lookup
+    # Only include monitored interfaces (nil treated as true for backwards compatibility)
     interface_capacity_map =
       device.interfaces
-      |> Enum.filter(& &1.monitored)
+      |> Enum.filter(&(&1.monitored != false))
       |> Map.new(fn interface ->
         cap = interface.configured_capacity_bps || interface.if_speed || 0
         {interface.id, {cap, cap}}