Add documentation for customizing health check tags

Author: Aaronontheweb

README.md

@@ -104,6 +104,32 @@ The health checks will automatically:
 
 Health checks are tagged with `akka`, `persistence`, and either `journal` or `snapshot-store` for filtering purposes.
 
+#### Customizing Health Check Tags
+
+You can customize the tags applied to health checks by providing an `IEnumerable<string>` to the `WithHealthCheck()` method:
+
+```csharp
+var host = new HostBuilder()
+    .ConfigureServices((context, services) => {
+        services.AddAkka("my-system-name", (builder, provider) =>
+        {
+            builder.WithSqlPersistence(
+                connectionString: _myConnectionString,
+                providerName: ProviderName.SqlServer2019,
+                journalBuilder: j => j.WithHealthCheck(
+                    unHealthyStatus: HealthStatus.Degraded,
+                    name: "sql-journal",
+                    tags: new[] { "backend", "database", "sql" }),
+                snapshotBuilder: s => s.WithHealthCheck(
+                    unHealthyStatus: HealthStatus.Degraded,
+                    name: "sql-snapshot",
+                    tags: new[] { "backend", "database", "sql" }));
+        });
+    });
+```
+
+When tags are not specified, the default tags are used: `["akka", "persistence", "journal"]` for journals and `["akka", "persistence", "snapshot-store"]` for snapshot stores.
+
 For ASP.NET Core applications, you can expose these health checks via an endpoint:
 
 ```csharp