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/common.rs

@@ -0,0 +1,34 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Shared resources found under bumble's common.py
+use pyo3::{PyObject, Python, ToPyObject};
+
+/// Represents the sink for some transport mechanism
+pub struct TransportSink(pub(crate) PyObject);
+
+impl ToPyObject for TransportSink {
+    fn to_object(&self, _py: Python<'_>) -> PyObject {
+        self.0.clone()
+    }
+}
+
+/// Represents the source for some transport mechanism
+pub struct TransportSource(pub(crate) PyObject);
+
+impl ToPyObject for TransportSource {
+    fn to_object(&self, _py: Python<'_>) -> PyObject {
+        self.0.clone()
+    }
+}