feat: member add logs, improve meta command

Catalogger.Backend/CataloggerMetrics.cs

@@ -1,9 +1,12 @@
+using NodaTime;
 using Prometheus;
 
 namespace Catalogger.Backend;
 
 public static class CataloggerMetrics
 {
+    public static Instant Startup { get; set; }
+
     public static readonly Gauge MessagesReceived =
         Metrics.CreateGauge("catalogger_received_messages", "Number of messages Catalogger has received");