Vendor dependencies

vendor/github.com/aws/smithy-go/middleware/eventstream_middleware.go

@@ -0,0 +1,21 @@
+package middleware
+
+type eventStreamOutputKey struct{}
+
+func AddEventStreamOutputToMetadata(metadata *Metadata, output any) {
+	metadata.Set(eventStreamOutputKey{}, output)
+}
+
+func GetEventStreamOutputToMetadata[T any](metadata *Metadata) (*T, bool) {
+	val := metadata.Get(eventStreamOutputKey{})
+	// not found
+	if val == nil {
+		return nil, false
+	}
+	// wrong type
+	res, ok := val.(*T)
+	if !ok {
+		return nil, false
+	}
+	return res, true
+}