[#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/Client.cs

@@ -0,0 +1,94 @@
+using System.Security.Cryptography;
+using FrostFS.Container;
+using FrostFS.Netmap;
+using FrostFS.SDK.Cryptography;
+using FrostFS.Session;
+using Grpc.Core;
+using Grpc.Net.Client;
+using Version = FrostFS.SDK.ModelsV2.Version;
+
+namespace FrostFS.SDK.ClientV2;
+
+public partial class Client
+{
+    private readonly ECDsa _key;
+    private GrpcChannel _channel;
+    private Version _version = new (2, 13);
+
+    private ContainerService.ContainerServiceClient _containerServiceClient;
+    private NetmapService.NetmapServiceClient _netmapServiceClient;
+    private SessionService.SessionServiceClient _sessionServiceClient;
+
+    public Client(string key, string host)
+    {
+        // TODO: Развязать клиент и реализацию GRPC
+        _key = key.LoadWif();
+        InitGrpcChannel(host);
+        InitContainerClient();
+        InitNetmapClient();
+        InitSessionClient();
+        CheckFrostFsVersionSupport();
+    }
+
+    private void CheckFrostFsVersionSupport()
+    {
+        var localNodeInfo = GetLocalNodeInfoAsync().Result;
+        var frostFsVersion = new Version(
+            (int)localNodeInfo.Body.Version.Major,
+            (int)localNodeInfo.Body.Version.Minor
+        );
+        if (!frostFsVersion.IsSupported(_version))
+        {
+            var msg = $"FrostFS {frostFsVersion} is not supported.";
+            Console.WriteLine(msg);
+            throw new ApplicationException(msg);
+        }
+    }
+
+    private void InitGrpcChannel(string host)
+    {
+        Uri uri;
+        try
+        {
+            uri = new Uri(host);
+        }
+        catch (UriFormatException e)
+        {
+            var msg = $"Host '{host}' has invalid format. Error: {e.Message}";
+            Console.WriteLine(msg);
+            throw new ArgumentException(msg);
+        }
+
+        ChannelCredentials grpcCredentials;
+        switch (uri.Scheme)
+        {
+            case "https":
+                grpcCredentials = ChannelCredentials.SecureSsl;
+                break;
+            case "http":
+                grpcCredentials = ChannelCredentials.Insecure;
+                break;
+            default:
+                var msg = $"Host '{host}' has invalid URI scheme: '{uri.Scheme}'.";
+                Console.WriteLine(msg);
+                throw new ArgumentException(msg);
+        }
+
+        _channel = GrpcChannel.ForAddress(uri, new GrpcChannelOptions { Credentials = grpcCredentials });
+    }
+
+    private void InitContainerClient()
+    {
+        _containerServiceClient = new ContainerService.ContainerServiceClient(_channel);
+    }
+
+    private void InitNetmapClient()
+    {
+        _netmapServiceClient = new NetmapService.NetmapServiceClient(_channel);
+    }
+
+    private void InitSessionClient()
+    {
+        _sessionServiceClient = new SessionService.SessionServiceClient(_channel);
+    }
+}