dns_update::Error does not implement std::error::Error

[jcgruenhage]

This makes usage in places where errors are expected to implement this trait difficult. The simplest patch for this would look like this:

commit b606c5a4964d0b2def6e13fa5c968d1da14ba0b2
Author: Jan Christian Grünhage <jan.christian@gruenhage.xyz>
Date:   Fri Oct 4 13:14:41 2024 +0200

    wip: improve error handling

diff --git a/Cargo.toml b/Cargo.toml
index 323dad8..1aaa8b0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,6 +19,7 @@ serde = { version = "1.0.197", features = ["derive"] }
 serde_json = "1.0.116"
 reqwest = { version = "0.12", default-features = false, features = ["rustls-tls-webpki-roots", "http2"]}
 serde_urlencoded = "0.7.1"
+thiserror = "1.0.64"
 
 [dev-dependencies]
 tokio = { version = "1", features = ["full"] }
diff --git a/src/lib.rs b/src/lib.rs
index fcb2354..a71781c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -23,11 +23,12 @@ use providers::{
     cloudflare::CloudflareProvider,
     rfc2136::{DnsAddress, Rfc2136Provider},
 };
+use thiserror::Error;
 
 pub mod http;
 pub mod providers;
 
-#[derive(Debug)]
+#[derive(Debug, Error)]
 pub enum Error {
     Protocol(String),
     Parse(String),

It probably makes sense to put a bit more effort into this and think about error handling.