Function buffer_prompt_until_connected 

fn buffer_prompt_until_connected(
    workspace: &Arc<Workspace>,
    sender: &SessionSlot,
    target_key: &SessionSlot,
    wrapped: WrappedPrompt,
) -> Option<WrappedPrompt>

Handle a Command::DeliverWorkerPrompt: route a wrapped peer-style envelope to the worker matching target_label in the caller’s project. Latest-spawned-wins on duplicate labels. The typed PeerEnvelopeAppended echo follows the same pattern as handle_deliver_peer_prompt - workers reuse the peer envelope verbatim so a view’s chat render is identical between the two paths.

Unlike handle_deliver_peer_prompt, this handler never buffers + auto-spawns: workers are only addressable while live. If the target label vanished between the dispatch and the handler firing (worker closed, lead cascade fired), the prompt is dropped with a warn log. Buffer wrapped on target_key’s DomainSession when the target hasn’t finished its Connected handshake (no session_id yet). Returns Some(wrapped) when the target IS connected (caller delivers now), or None when it parked (the target’s Connected handler drains the bucket, doing the render + dispatch). Mirrors the sleeping-peer buffering in handle_deliver_peer_prompt, sender included so an expired bucket can still acknowledge the message.