test: enforce participant-bound observer lifecycle

cai

2026-08-08 58946662462ac8d9a610b72ce19090ecb0d4b5f2

 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,