Restructure solution layout by module

src/Registry/StellaOps.Registry.TokenService/Observability/RegistryTokenMetrics.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Diagnostics.Metrics;
+
+namespace StellaOps.Registry.TokenService.Observability;
+
+public sealed class RegistryTokenMetrics : IDisposable
+{
+    public const string MeterName = "StellaOps.Registry.TokenService";
+
+    private readonly Meter _meter;
+    private bool _disposed;
+
+    public RegistryTokenMetrics()
+    {
+        _meter = new Meter(MeterName);
+        TokensIssued = _meter.CreateCounter<long>("registry_token_issued_total", unit: "tokens", description: "Total tokens issued grouped by plan.");
+        TokensRejected = _meter.CreateCounter<long>("registry_token_rejected_total", unit: "tokens", description: "Total token requests rejected grouped by reason.");
+    }
+
+    public Counter<long> TokensIssued { get; }
+
+    public Counter<long> TokensRejected { get; }
+
+    public void Dispose()
+    {
+        if (_disposed)
+        {
+            return;
+        }
+
+        _meter.Dispose();
+        _disposed = true;
+    }
+}