trait-based APIs defined local to a function don't compile

I expected this to succeed:

fn main() {
    #[dropshot::api_description]
    trait MyApi {
        type Context;
    }
    let description = my_api_mod::stub_api_description().unwrap();
    let spec = description.openapi("Counter Server", "1.0.0");
    println!(
        "{}",
        serde_json::to_string_pretty(&spec.json().unwrap()).unwrap()
    );
}

Instead it fails with:

$ cargo run --example=api-trait-broken
   Compiling dropshot v0.12.1-dev (/Users/dap/oxide/dropshot-operation-id/dropshot)
error[E0405]: cannot find trait `MyApi` in this scope
 --> dropshot/examples/api-trait-broken.rs:3:11
  |
3 |     trait MyApi {
  |           ^^^^^ not found in this scope

For more information about this error, try `rustc --explain E0405`.
error: could not compile `dropshot` (example "api-trait-broken") due to 1 previous error

Start with dropshot/examples/api-trait-broken.rs and the #[dropshot::api_description] entry point. Run cargo run --example=api-trait-broken to reproduce the local-trait compilation failure, then trace how the macro generates my_api_mod::stub_api_description(). Done means the example compiles and prints the generated OpenAPI JSON.