Add licensing info to backend files

src/backend/mod.rs

@@ -1,3 +1,6 @@
+// Copyright (c) 2022 Marceline Cramer
+// SDPX-License-Identifier: LGPL-3.0-or-later
+
 //! This module defines backends for WebAssembly execution.
 //!
 //! Canary is designed to support multiple WebAssembly runtimes for different

src/backend/wasmtime.rs

@@ -1,3 +1,6 @@
+// Copyright (c) 2022 Marceline Cramer
+// SDPX-License-Identifier: LGPL-3.0-or-later
+
 use std::ops::DerefMut;
 
 use super::{Arc, Backend, Instance, PanelId};