chore: import upstream snapshot with attribution

dotnet/samples/Demos/VectorStoreRAG/Options/CosmosConfig.cs

@@ -0,0 +1,20 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.ComponentModel.DataAnnotations;
+
+namespace VectorStoreRAG.Options;
+
+/// <summary>
+/// Azure CosmosDB service settings for use with CosmosMongo and CosmosNoSql.
+/// </summary>
+internal sealed class CosmosConfig
+{
+    public const string MongoConfigSectionName = "CosmosMongoDB";
+    public const string NoSqlConfigSectionName = "CosmosNoSql";
+
+    [Required]
+    public string ConnectionString { get; set; } = string.Empty;
+
+    [Required]
+    public string DatabaseName { get; set; } = string.Empty;
+}