fix(transport): harden QUIC admission boundaries

core/src/wire.rs

@@ -388,6 +388,7 @@ impl ConnectionManifest {
                 .iter()
                 .any(|address| !bounded(address, 1, 256))
             || !valid_dns_name(&self.gateway.public_identity)
+            || self.gateway.public_identity == self.gateway.id
             || !(1..=4).contains(&self.tunnel.versions.len())
             || self
                 .tunnel
@@ -621,6 +622,7 @@ struct StableError {
 
 pub(crate) struct DecodedStableError {
     pub(crate) error: CoreError,
+    pub(crate) code: String,
     pub(crate) retryable: bool,
 }
 
@@ -703,6 +705,7 @@ pub(crate) fn decode_stable_error(bytes: &[u8]) -> Result<DecodedStableError> {
     };
     Ok(DecodedStableError {
         error,
+        code: stable.code,
         retryable: stable.retryable,
     })
 }