Add support for nonisolated(nonsending) by default

Examples/Streaming+Codable/Package.swift

@@ -19,14 +19,16 @@ let package = Package(
             dependencies: [
                 .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
                 .product(name: "AWSLambdaEvents", package: "swift-aws-lambda-events"),
-            ]
+            ],
+            swiftSettings: [.enableExperimentalFeature("NonisolatedNonsendingByDefault")]
         ),
         .testTarget(
             name: "Streaming+CodableTests",
             dependencies: [
                 "StreamingCodable",
                 .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
-            ]
+            ],
+            swiftSettings: [.enableUpcomingFeature("NonisolatedNonsendingByDefault")]
         ),
     ]
 )

Package.swift

@@ -6,7 +6,9 @@ let defaultSwiftSettings: [SwiftSetting] =
     [
         .enableExperimentalFeature(
             "AvailabilityMacro=LambdaSwift 2.0:macOS 15.0"
-        )
+        ),
+        .enableUpcomingFeature("NonisolatedNonsendingByDefault"),
+        .enableUpcomingFeature("InferIsolatedConformances"),
     ]
 
 let package = Package(

Sources/AWSLambdaRuntime/LambdaHandlers.swift

@@ -48,7 +48,7 @@ public protocol StreamingLambdaHandler: _Lambda_SendableMetatype {
 
 /// A writer object to write the Lambda response stream into. The HTTP response is started lazily.
 /// before the first call to ``write(_:)`` or ``writeAndFinish(_:)``.
-public protocol LambdaResponseStreamWriter {
+public protocol LambdaResponseStreamWriter: Sendable {
     /// Write a response part into the stream. Bytes written are streamed continually.
     /// - Parameter buffer: The buffer to write.
     /// - Parameter hasCustomHeaders: If `true`, the response will be sent with custom HTTP status code and headers.