misc improvements to cli (#2827)

* misc improvements to cli

* switch host shorthand to H

* simplify macro

core/startos/src/util/mod.rs

@@ -648,7 +648,7 @@ impl<'a, T> From<&'a T> for MaybeOwned<'a, T> {
 pub fn new_guid() -> InternedString {
     use rand::RngCore;
     let mut buf = [0; 20];
-    rand::thread_rng().fill_bytes(&mut buf);
+    rand::rng().fill_bytes(&mut buf);
     InternedString::intern(base32::encode(
         base32::Alphabet::Rfc4648 { padding: false },
         &buf,