refactor(tests): replace temporary variable pointer pattern with new() builtin

Simplify device update test by using new(false) and new(int32(10)) instead
of declaring named sync variables and taking their addresses.

cmd/server/tests/device_test.go

@@ -147,12 +147,10 @@ func TestUpdateDevice(t *testing.T) {
 	device := setup.CreateDevice(t, "Test Device", "koreader", "test-device-123")
 
 	// Update device
-	syncEnabled := false
-	syncFreq := int32(10)
 	updateRequest := handlers.DeviceUpdateRequest{
 		DeviceName:           "Updated Device Name",
-		SyncEnabled:          &syncEnabled,
-		SyncFrequencyMinutes: &syncFreq,
+		SyncEnabled:          new(false),
+		SyncFrequencyMinutes: new(int32(10)),
 	}
 	updateBody, _ := json.Marshal(updateRequest)