Function prepare 

pub fn prepare(
    services: Option<FeedbackServices>,
    device: &str,
    author: &str,
    instance: u64,
) -> Result<AppComponent, LaunchError>

Prepare the chrome component over an isolated, ephemeral store. The host’s durable outbox is lent separately; raw drafts cannot reach profile records, history or room synchronization through this preparation path.

Errors

Reports invalid host identity or component admission failure.