[#24] Client: Implement pool part1

first iteration - base classes and methods

Signed-off-by: Pavel Gross <p.gross@yadro.com>

src/FrostFS.SDK.ClientV2/Caches.cs

@@ -0,0 +1,22 @@
+using Microsoft.Extensions.Caching.Memory;
+
+namespace FrostFS.SDK.ClientV2;
+
+internal static class Caches
+{
+    private static readonly IMemoryCache _ownersCache = new MemoryCache(new MemoryCacheOptions
+    {
+        // TODO: get from options?
+        SizeLimit = 256
+    });
+
+    private static readonly IMemoryCache _containersCache = new MemoryCache(new MemoryCacheOptions
+    {
+        // TODO: get from options?
+        SizeLimit = 1024
+    });
+
+    internal static IMemoryCache Owners => _ownersCache;
+
+    internal static IMemoryCache Containers => _containersCache;
+}