Refactor embedding request creation and processing

Consolidate embedding request logic into a new EmbeddingRequest record with static factory methods for IFormFile and stream input. Remove FormFileToEmbeddingRequestExecutor and FormFileEmbeddingRequest, updating all usages and dependency injection accordingly. Clean up related code in Program.cs, VectorSearchService, and _Imports.razor. Enhance XML documentation for EmbeddingRequest to clarify intent and usage.

SqlDatabaseVectorSearch/Workflows/EmbeddingRequest.cs

@@ -0,0 +1,26 @@
+namespace SqlDatabaseVectorSearch.Workflows;
+
+public record class EmbeddingRequest(Stream Content, string FileName, string ContentType, Guid? DocumentId)
+{
+    /// <summary>
+    /// Creates an <see cref="EmbeddingRequest"/> from an uploaded <see cref="IFormFile"/>.
+    /// </summary>
+    /// <param name="file">The uploaded file.</param>
+    /// <param name="documentId">The optional identifier of the document to overwrite.</param>
+    public static EmbeddingRequest FromFormFile(IFormFile file, Guid? documentId = null) => Create(file.OpenReadStream(), Path.GetFileName(file.FileName), documentId);
+
+    /// <summary>
+    /// Creates an <see cref="EmbeddingRequest"/> from a content stream, inferring the content type from the file name.
+    /// </summary>
+    /// <param name="content">The stream that contains the document content.</param>
+    /// <param name="fileName">The name of the document.</param>
+    /// <param name="documentId">The optional identifier of the document to overwrite.</param>
+    /// <remarks>
+    /// The content type is inferred from the file name because the content type declared by the client is not always reliable (for example, for Markdown files).
+    /// </remarks>
+    public static EmbeddingRequest Create(Stream content, string fileName, Guid? documentId = null)
+    {
+        var name = Path.GetFileName(fileName);
+        return new EmbeddingRequest(content, name, MimeMapping.MimeUtility.GetMimeMapping(name), documentId);
+    }
+}

SqlDatabaseVectorSearch/Workflows/FormFileToEmbeddingRequestExecutor.cs

@@ -1,18 +0,0 @@
-using Microsoft.Agents.AI.Workflows;
-
-namespace SqlDatabaseVectorSearch.Workflows;
-
-public partial class FormFileToEmbeddingRequestExecutor() : Executor(nameof(FormFileToEmbeddingRequestExecutor))
-{
-    [MessageHandler]
-    private ValueTask<EmbeddingRequest> HandleAsync(FormFileEmbeddingRequest request, IWorkflowContext context, CancellationToken cancellationToken)
-    {
-        // Note: file.ContentType is not 100% reliable (for example, for markdown file).
-        var embeddingRequest = new EmbeddingRequest(request.File.OpenReadStream(), Path.GetFileName(request.File.FileName), MimeMapping.MimeUtility.GetMimeMapping(request.File.FileName), request.DocumentId);
-        return ValueTask.FromResult(embeddingRequest);
-    }
-}
-
-public record class FormFileEmbeddingRequest(IFormFile File, Guid? DocumentId);
-
-public record class EmbeddingRequest(Stream Content, string FileName, string ContentType, Guid? DocumentId);