chore: import upstream snapshot with attribution

dotnet/samples/Demos/VectorStoreRAG/TextSnippet.cs

@@ -0,0 +1,36 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Microsoft.Extensions.VectorData;
+using Microsoft.SemanticKernel.Data;
+
+namespace VectorStoreRAG;
+
+/// <summary>
+/// Data model for storing a section of text with an embedding and an optional reference link.
+/// </summary>
+/// <typeparam name="TKey">The type of the data model key.</typeparam>
+internal sealed class TextSnippet<TKey>
+{
+    [VectorStoreKey]
+    public required TKey Key { get; set; }
+
+    [TextSearchResultValue]
+    [VectorStoreData]
+    public string? Text { get; set; }
+
+    [TextSearchResultName]
+    [VectorStoreData]
+    public string? ReferenceDescription { get; set; }
+
+    [TextSearchResultLink]
+    [VectorStoreData]
+    public string? ReferenceLink { get; set; }
+
+    /// <summary>
+    /// The text embedding for this snippet. This is used to search the vector store.
+    /// While this is a string property it has the vector attribute, which means whatever
+    /// text it contains will be converted to a vector and stored as a vector in the vector store.
+    /// </summary>
+    [VectorStoreVector(1536)]
+    public string? TextEmbedding => this.Text;
+}