feat: initial commit

reach/client/protocol/protocol.go

@@ -0,0 +1,13 @@
+package protocol
+
+import (
+	"context"
+)
+
+type Identifier string
+
+type Protocol interface {
+	Identifier() Identifier
+	Available(ctx context.Context, addr string) (bool, error)
+	Operations(addr string) Operations
+}