update Response API

src/client/connection/response/failure/error.rs

@@ -0,0 +1,28 @@
+use std::fmt::{Display, Formatter, Result};
+
+#[derive(Debug)]
+pub enum Error {
+    Code(u8),
+    Permanent(super::permanent::Error),
+    Protocol,
+    Temporary(super::temporary::Error),
+}
+
+impl Display for Error {
+    fn fmt(&self, f: &mut Formatter) -> Result {
+        match self {
+            Self::Code(e) => {
+                write!(f, "Code group error: {e}*")
+            }
+            Self::Permanent(e) => {
+                write!(f, "Permanent failure group error: {e}")
+            }
+            Self::Protocol => {
+                write!(f, "Protocol error")
+            }
+            Self::Temporary(e) => {
+                write!(f, "Temporary failure group error: {e}")
+            }
+        }
+    }
+}