build: Add "io" module for BLE/ UART messages

build.rs

@@ -1,6 +1,6 @@
 use std::env;
 
-fn main() {
+fn main() -> std::io::Result<()> {
     let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap();
 
     if target_arch == "riscv32" {
@@ -8,6 +8,16 @@ fn main() {
         // make sure linkall.x is the last linker script (otherwise might cause problems with flip-link)
         println!("cargo:rustc-link-arg=-Tlinkall.x");
     }
+
+    let descriptor_path =
+        std::path::PathBuf::from(env::var("OUT_DIR").unwrap()).join("proto_descriptor.bin");
+
+    prost_build::Config::new()
+        .file_descriptor_set_path(&descriptor_path)
+        .compile_well_known_types()
+        .compile_protos(&["docs/c_its-messages.proto"], &["docs/"])?;
+
+    Ok(())
 }
 
 fn linker_be_nice() {