Refactor data providers and update abstractions

- Removed obsolete data providers: `AnchorCollectionDataProvider`, `ContentsDataProvider`, and others, consolidating logic into new composable providers.
- Added `ComposeDataProviders`, `SelectDataProvider`, and `RelationalDataProvider` for improved flexibility and reusability.
- Introduced `IManySelectionComposableDataProvider` interface to support multiple-node selection.
- Enhanced `UnitDownloader` with more robust progress tracking.
- Updated package references and project dependencies for consistency.
- Improved error handling in `StealthConfig` initialization for better fallback on browser drivers.
- Incremented project version to 2.4.5.

Beam.Api/ApiResponse.cs

@@ -1,10 +1,15 @@
-using Microsoft.Extensions.Logging;
+using System;
+using System.IO;
+using Microsoft.Extensions.Logging;
 using System.Net;
+using System.Net.Http;
 using System.Net.Http.Json;
 using System.Text;
 using System.Text.Json;
+using System.Threading;
+using System.Threading.Tasks;
 
-namespace Beam { 
+namespace Beam.Api;
     /// <summary>
     /// Wrapper that lets the response body be read any number of times (even concurrently).
     /// </summary>
@@ -78,5 +83,4 @@ namespace Beam {
             if (!Is200) Logger?.LogWarning("Non-success response; attempting to read content.");
             return Task.FromResult<Stream>(new MemoryStream(_buffer, writable: false));
         }
-    }
 }