Append when the GeoFeed is retrieved and if it was generated from in memory cache

AS1024.GeoFeed.MinimalAPI/Program.cs

@@ -55,10 +55,12 @@ namespace AS1024.GeoFeed.MinimalAPI
                 IMemoryCache memoryCache,
                 IWebHostEnvironment environment)
         {
+            bool isCached = true;
             try
             {
                 if (!memoryCache.TryGetValue("Geofeed", out List<IPGeoFeed>? feed))
                 {
+                    isCached = false;
                     feed = await provider.GetGeoFeedData();
                     if (environment.IsProduction())
                     {
@@ -68,7 +70,7 @@ namespace AS1024.GeoFeed.MinimalAPI
                     }
                 }
 
-                return Results.File(Encoding.UTF8.GetBytes(feed.ToGeoFeedCsv()),
+                return Results.File(Encoding.UTF8.GetBytes(feed.ToGeoFeedCsv(true, isCached)),
                     "text/csv",
                     "geofeed.csv");