feat(metrics): Add queried-tracks metric

src/Lavalink4NET.Rest/LavalinkApiClient.cs

@@ -1,6 +1,7 @@
 namespace Lavalink4NET.Rest;
 
 using System.Collections.Immutable;
+using System.Diagnostics.Metrics;
 using System.Net;
 using System.Net.Http;
 using System.Net.Http.Json;
@@ -242,6 +243,9 @@ private async ValueTask<LoadResultModel> LoadTracksInternalAsync(string identifi
         cancellationToken.ThrowIfCancellationRequested();
         ArgumentNullException.ThrowIfNull(identifier);
 
+        var metricTag = KeyValuePair.Create<string, object?>("Identifier", identifier);
+        Diagnostics.QueriedTracks.Add(1, metricTag);
+
         var queryParameters = HttpUtility.ParseQueryString(string.Empty);
         queryParameters["identifier"] = identifier;
 
@@ -500,4 +504,19 @@ private static string PrefixIdentifier(string identifier, TrackSearchMode search
             ? identifier
             : $"{searchMode.Prefix}:{identifier}";
     }
+}
+
+file static class Diagnostics
+{
+    public static Counter<long> QueriedTracks { get; }
+
+    static Diagnostics()
+    {
+        var meter = new Meter("Lavalink4NET");
+
+        QueriedTracks = meter.CreateCounter<long>(
+            name: "queried-tracks",
+            unit: "Tracks",
+            description: "The number of tracks queried from the node (non-cached only).");
+    }
 }

src/Lavalink4NET/Tracks/TrackManager.cs

@@ -1,4 +1,5 @@
 namespace Lavalink4NET.Tracks;
+
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.Metrics;
@@ -145,7 +146,7 @@ static Diagnostics()
         ResolvedTracks = meter.CreateCounter<long>(
             name: "resolved-tracks",
             unit: "Tracks",
-            description: "The number of resolved tracks.");
+            description: "The number of resolved tracks (including cached and non-cached).");
 
         FailedQueries = meter.CreateCounter<long>(
             name: "failed-queries",