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.Dynamic/DataProviders/ComposeDataProviders.cs

@@ -0,0 +1,83 @@
+using Beam.Abstractions;
+using HtmlAgilityPack;
+
+namespace Beam.Dynamic;
+
+/// <summary>
+/// Allows composition of different data providers to adapt to different types of data.
+/// </summary>
+/// <typeparam name="T"></typeparam>
+public class ComposeDataProviders<T> : IComposableDataProvider<T> {
+    public required IComposableDataProvider<object>[] SelectWith { get; init; }
+    public required IComposableDataProvider<T> GetWith { get; init; }
+    
+    private ComposeDataProviders() {}
+
+    public static ComposeDataProviders<T> Create(IComposableDataProvider<object> selectWith, IComposableDataProvider<T> getWith) {
+        return new ComposeDataProviders<T>() {
+            GetWith = getWith,
+            SelectWith = [selectWith]
+        };
+    }
+
+    public static ComposeDataProviders<T> Create(IComposableDataProvider<object>[] selectWiths, IComposableDataProvider<T> getWith) {
+        return new ComposeDataProviders<T>() {
+            GetWith = getWith,
+            SelectWith = selectWiths
+        };
+    }
+
+    /// <summary>
+    /// Composes the data providers, first selecting a node with <see cref="SelectWith"/>, then getting the data with <see cref="GetWith"/>.
+    /// </summary>
+    /// <exception cref="Exception">Throws when <see cref="SelectWith"/> returns a null value.</exception>
+    /// <param name="document"></param>
+    /// <returns></returns>
+    public T Get(HtmlDocument document) {
+        var selected = Select(document);
+        if (selected is null)
+            throw new Exception("Selection operation failed.");
+        return GetWith.Get(selected);
+    }
+    
+    /// <summary>
+    /// Uses the <see cref="GetWith"/> data provider to get the data from the supplied node.
+    /// </summary>
+    /// <param name="node"></param>
+    /// <returns></returns>
+    public T Get(HtmlNode node) {
+        return GetWith.Get(node);
+    }
+    
+    /// <summary>
+    /// Uses the <see cref="SelectWith"/> data provider to select a node from the supplied document.
+    /// </summary>
+    /// <param name="doc"></param>
+    /// <returns></returns>
+    public HtmlNode? Select(HtmlDocument doc) {
+        var selected = SelectWith[0].Select(doc);
+        foreach(var provider in SelectWith.Skip(1)) {
+            if (selected is null)
+                return null;
+            selected = provider.Select(selected);
+        }
+
+        return selected;
+    }
+
+    /// <summary>
+    /// Uses the <see cref="SelectWith"/> data provider to select a node from the supplied document.
+    /// </summary>
+    /// <param name="doc"></param>
+    /// <returns></returns>
+    public HtmlNode? Select(HtmlNode node) {
+        var selected = SelectWith[0].Select(node);
+        foreach(var provider in SelectWith.Skip(1)) {
+            if (selected is null)
+                return null;
+            selected = provider.Select(selected);
+        }
+
+        return selected;
+    }
+}