xenstore: use AsRef<str> for path and restructure

crates/xen/xenstore/examples/list.rs

@@ -1,7 +1,7 @@
 use std::env::args;
 
-use xenstore::client::{XsdClient, XsdInterface};
 use xenstore::error::Result;
+use xenstore::{XsdClient, XsdInterface};
 
 async fn list_recursive(client: &XsdClient, path: &str) -> Result<()> {
     let mut pending = vec![path.to_string()];

crates/xen/xenstore/examples/watch.rs

@@ -1,6 +1,6 @@
 use std::env::args;
-use xenstore::client::XsdClient;
 use xenstore::error::Result;
+use xenstore::XsdClient;
 
 #[tokio::main]
 async fn main() -> Result<()> {