docs(wireguard-broker): add docs and examples

wireguard-broker/src/api/mod.rs

@@ -1,3 +1,9 @@
+//! This module implements the binary WireGuard broker protocol in the form of the [client::BrokerClient]
+//! and the [server::BrokerServer].
+//!
+//! Specifically, The protocol enables the client to tell the server to set a pre-shared key for a
+//! wireguard interface.
+
 pub mod client;
 pub mod config;
 pub mod msgs;