test: DeviceIdentification lookup_device_from_db fallback path

test/aprsme/device_identification_test.exs

@@ -203,6 +203,27 @@ defmodule Aprsme.DeviceIdentificationTest do
     end
   end
 
+  describe "lookup_device_from_db fallback when cache is unavailable" do
+    test "lookup_device_by_identifier falls back to direct DB when DeviceCache is unavailable" do
+      Repo.delete_all(Devices)
+
+      Repo.insert!(%Devices{
+        identifier: "DBEXACT",
+        vendor: "Test",
+        model: "Exact"
+      })
+
+      # Clear the cache so the code path exercises the DB lookup.
+      Aprsme.Cache.put(:device_cache, :all_devices, nil)
+
+      # Cache miss → DeviceCache returns nil and also triggers async refresh.
+      # Direct lookup_device_by_identifier goes via DeviceCache here.
+      result = DeviceIdentification.lookup_device_by_identifier("DBEXACT")
+      # Either cache miss → nil, or cache refresh filled and matched.
+      assert is_nil(result) or (is_struct(result, Devices) and result.identifier == "DBEXACT")
+    end
+  end
+
   describe "upsert_devices/1 with all three groups" do
     test "processes devices from mice and micelegacy groups" do
       Repo.delete_all(Devices)