add jwt files

providers/single_flight/flight.go

@@ -0,0 +1,18 @@
+package single_flight
+
+import (
+	"atom/container"
+	"log"
+
+	"golang.org/x/sync/singleflight"
+)
+
+func init() {
+	if err := container.Container.Provide(NewSingleFlight); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func NewSingleFlight() (*singleflight.Group, error) {
+	return &singleflight.Group{}, nil
+}