[#1] Define SDK structure

TODO: Вынести маппинг модель -> grpc в отдельный слой

Signed-off-by: Ivan Pchelintsev <i.pchelintsev@yadro.com>

sdk/src/FrostFS.SDK.ClientV2/RequestConstructor.cs

@@ -0,0 +1,26 @@
+using FrostFS.SDK.ModelsV2;
+using FrostFS.Session;
+
+namespace FrostFS.SDK.ClientV2;
+
+public static class RequestConstructor
+{
+    public static void AddMetaHeader(this IRequest request, MetaHeader? metaHeader = null)
+    {
+        if (request.MetaHeader is not null) return;
+        
+        metaHeader ??= MetaHeader.Default();
+
+        request.MetaHeader = new RequestMetaHeader
+        {
+            Version = new Refs.Version
+            {
+                Major = (uint)metaHeader.Version.Major,
+                Minor = (uint)metaHeader.Version.Minor,
+
+            },
+            Epoch = (uint)metaHeader.Epoch,
+            Ttl = (uint)metaHeader.Ttl
+        };
+    }
+}