Function native_callback 

pub async fn native_callback(
    __arg0: Query<NativePollQuery>,
) -> Result<Response, AuthError>

Direct-hit fallback for the registered native redirect_uri. In the real flow this path is never dereferenced by an actual browser redirect — the upstream provider’s redirect target is always its own /auth/<provider>/callback (e.g. /auth/google/callback, /auth/github/callback), which detects a native-flow authorization request and short-circuits into stashing the code for /native/poll instead of redirecting here. This handler only answers a stray direct visit (e.g. a stale bookmark or a misconfigured client), so state is validated for URL-shape consistency but deliberately not looked up — there’s nothing to correlate it against.