Use secure DNS for websocket connection establishment (#5386)

implementation of secure dns for websocket connection establishment. depends on #5355

common/http-api-client/src/dns.rs

@@ -40,6 +40,7 @@ struct SocketAddrs {
 
 #[derive(Debug, thiserror::Error)]
 #[error("hickory-dns resolver error: {hickory_error}")]
+/// Error occurring while resolving a hostname into an IP address.
 pub struct HickoryDnsError {
     #[from]
     hickory_error: ResolveError,

common/http-api-client/src/lib.rs

@@ -22,7 +22,7 @@ pub use user_agent::UserAgent;
 #[cfg(not(target_arch = "wasm32"))]
 mod dns;
 #[cfg(not(target_arch = "wasm32"))]
-pub use dns::HickoryDnsResolver;
+pub use dns::{HickoryDnsError, HickoryDnsResolver};
 
 // The timeout is relatively high as we are often making requests over the mixnet, where latency is
 // high and chatty protocols take a while to complete.