Ability to send HCI commands from Rust

* Autogenerate packet code in Rust from PDL (packet file copied from rootcanal)
* Implement parsing of packets that have a type header
* Expose Python APIs for sending HCI commands
* Expose Python APIs for instantiating a local controller

rust/src/wrapper/host.rs

@@ -15,7 +15,7 @@
 //! Host-side types
 
 use crate::wrapper::transport::{Sink, Source};
-use pyo3::{intern, prelude::PyModule, types::PyDict, PyObject, PyResult, Python};
+use pyo3::{intern, prelude::PyModule, types::PyDict, PyObject, PyResult, Python, ToPyObject};
 
 /// Host HCI commands
 pub struct Host {
@@ -61,6 +61,12 @@ impl Host {
     }
 }
 
+impl ToPyObject for Host {
+    fn to_object(&self, _py: Python<'_>) -> PyObject {
+        self.obj.clone()
+    }
+}
+
 /// Driver factory to use when initializing a host
 #[derive(Debug, Clone)]
 pub enum DriverFactory {