test: exercise live VAD session metadata boundary

cai

2026-08-08 2fe34384cd7519f1aebb5f3ac818fe008541e0a6

 src/asr_realtime.rs

@@ -106,9 +106,7 @@
        F: FnOnce() -> HashMap<String, String>,
    {
        let metadata = AudioIngressMetadata::from_participant(&read_attributes())
            .map_err(|reason| anyhow!(reason))
            .ok()
            .flatten();
            .map_err(|reason| anyhow!(reason))?;
        Self::start(
            http,
            config,