refactor: remove unnecessary await Task.CompletedTask from async iterators

Co-authored-by: petesramek <2333452+petesramek@users.noreply.github.com>
Agent-Logs-Url: https://github.com/petesramek/polyline-algorithm-csharp/sessions/8bac762b-8608-43c2-9c46-e9485c2acf63

Author: Copilot

src/PolylineAlgorithm/Abstraction/AbstractPolylineDecoder.cs

@@ -167,8 +167,6 @@ public async IAsyncEnumerable<TCoordinate> DecodeAsync(
             cancellationToken.ThrowIfCancellationRequested();
             yield return coordinate;
         }
-
-        await Task.CompletedTask.ConfigureAwait(false);
     }
 
     /// <summary>

src/PolylineAlgorithm/Extensions/AsyncPolylineEncoderExtensions.cs

@@ -59,7 +59,5 @@ private static async IAsyncEnumerable<Coordinate> ToAsyncEnumerable(
             cancellationToken.ThrowIfCancellationRequested();
             yield return item;
         }
-
-        await System.Threading.Tasks.Task.CompletedTask.ConfigureAwait(false);
     }
 }

tests/PolylineAlgorithm.Tests/AsyncPolylineEncoderTest.cs

@@ -144,7 +144,5 @@ private static async IAsyncEnumerable<Coordinate> ToAsyncEnumerable(IEnumerable<
         foreach (var item in source) {
             yield return item;
         }
-
-        await Task.CompletedTask;
     }
 }

tests/PolylineAlgorithm.Tests/PolylinePipeEncoderTest.cs

@@ -133,7 +133,5 @@ private static async IAsyncEnumerable<Coordinate> ToAsyncEnumerable(IEnumerable<
         foreach (var item in source) {
             yield return item;
         }
-
-        await Task.CompletedTask;
     }
 }