Trying adding of metadata field

Author: Matthew Harris

src/Azure.AISearch.WebApp/Services/AzureCognitiveSearchConfigurationService.cs

@@ -157,6 +157,8 @@ private async Task CreateDocumentsIndex(AppSettingsOverride? settingsOverride, s
                 new FieldMapping("content") { TargetFieldName = nameof(Document.Content) },
                 // Map the full blob URL as the document file path.
                 new FieldMapping("metadata_storage_path") { TargetFieldName = nameof(Document.FilePath) }
+                // mjh Map the data source custom metadata field on the blob
+                new FieldMapping("data_source") { TargetFieldName = nameof(Document.DataSource) }
             },
             // Use the skillset for chunking and embedding.
             SkillsetName = skillset.Name