Add a CacheNames property to IFusionCacheProvider

Note: this is a breaking change since it adds an interface member.

src/ZiggyCreatures.FusionCache/IFusionCacheProvider.cs

@@ -1,4 +1,6 @@
-namespace ZiggyCreatures.Caching.Fusion;
+using System.Collections.Generic;
+
+namespace ZiggyCreatures.Caching.Fusion;
 
 /// <summary>
 /// The provider to work with multiple named FusionCache instances, kinda like Microsoft's HTTP named clients (see https://learn.microsoft.com/en-us/aspnet/core/fundamentals/http-requests#named-clients)
@@ -18,4 +20,9 @@ public interface IFusionCacheProvider
 	/// <param name="cacheName">The name of the cache: it must match the one provided during registration.</param>
 	/// <returns>The FusionCache instance corresponding to the cache name specified.</returns>
 	IFusionCache? GetCacheOrNull(string cacheName);
+
+	/// <summary>
+	/// The collection of all available FusionCache names.
+	/// </summary>
+	IReadOnlyCollection<string> CacheNames { get; }
 }

src/ZiggyCreatures.FusionCache/Internals/Provider/FusionCacheProvider.cs

@@ -59,4 +59,6 @@ public IFusionCache GetCache(string cacheName)
 			: $"No cache has been registered with name ({cacheName}): make sure you registered it with the AddFusionCache(\"{cacheName}\") method."
 		);
 	}
+
+	public IReadOnlyCollection<string> CacheNames => _lazyNamedCaches.Select(e => e.CacheName).ToList();
 }