Refactor fluent download pipelines

Beam.Fluent/Core/FragmentMode.cs

@@ -0,0 +1,17 @@
+namespace Beam.Fluent;
+
+public enum FragmentMode {
+    Single,
+    Fragmented
+}
+
+public enum Channel {
+    Plain,
+    Stealth,
+    Playwright
+}
+
+public enum ContentKind {
+    Html,
+    Binary
+}

Beam.Fluent/Core/IContextStage.cs

@@ -0,0 +1,18 @@
+using Beam.Abstractions;
+using Beam.Downloaders;
+using Beam.Models;
+using Beam.Playwright;
+using Beam.Stealth;
+
+namespace Beam.Fluent;
+
+public interface IContextStage<RawType, OutType> {
+    IContextStage<RawType, OutType> Configure(Action<DownloadContextBuilder<RawType>> configure);
+    IContextStage<RawType, OutType> WithParallelism(int degree);
+    IContextStage<RawType, OutType> WithTimeout(TimeSpan timeout);
+    IContextStage<RawType, OutType> WithRetryReporter(IProgress<IRetryReport> reporter);
+    IContextStage<RawType, OutType> UseFragments();
+    IContextStage<RawType, OutType> UsePlaywright(PlaywrightAsyncManipulator manipulator);
+    IContextStage<RawType, OutType> UseStealth(StealthAsyncManipulator manipulator, StealthConfig config);
+    DownloadEnumerable<OutType> Build();
+}

Beam.Fluent/Core/IDownloadStage.cs

@@ -0,0 +1,12 @@
+using System.Collections.Concurrent;
+
+namespace Beam.Fluent;
+
+public interface IDownloadStage<RawType, OutType> {
+    IDownloadStage<RawType, OutType> SaveToDirectory(string dir);
+    IDownloadStage<RawType, OutType> SaveToFiles(IEnumerable<string> files);
+    IDownloadStage<RawType, OutType> SaveToMemory(ConcurrentBag<OutType> bag);
+    void WaitForDownload();
+    Task WaitForDownloadAsync();
+    DownloadEnumerable<OutType> AsAsyncEnumerable();
+}

Beam.Fluent/Core/ITransformStage.cs

@@ -0,0 +1,8 @@
+using Beam.Dynamic;
+using Beam.Models;
+
+namespace Beam.Fluent;
+
+public interface ITransformStage<RawType, OutType> {
+    IContextStage<RawType, OutType> WithTransformer(AsyncTransformer<RawType, OutType> factory);
+}