feat: move client decode library into a feature

breaking change: Client features must be be built specificially and are not included by default.

src/lib.rs

@@ -2,12 +2,15 @@
 #![allow(non_camel_case_types)]
 
 pub mod aztec;
-pub mod client;
+
 pub mod common;
 mod exceptions;
 pub mod maxicode;
 pub mod qrcode;
 
+#[cfg(feature = "client_support")]
+pub mod client;
+
 use std::{collections::HashMap, rc::Rc};
 
 pub use exceptions::Exceptions;