[#30] Client: Add object model for Rules

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

src/FrostFS.SDK.Tests/Unit/PlacementVectorTests.cs

@@ -35,7 +35,7 @@ public class PlacementVectorTests(ITestOutputHelper testOutputHelper)
             //if (!file.EndsWith("selector_invalid.json"))
             //    continue;
 
-            var fileName = file[(file.LastIndexOf("..\\") + 3)..];
+            var fileName = file[(file.LastIndexOf("..\\", StringComparison.OrdinalIgnoreCase) + 3)..];
             _testOutputHelper.WriteLine($"Open file {fileName}");
 
             var str = File.ReadAllText(file);