Update dashboard support for uninstrumented peers to support non-leaf spans

Update dashboard support for uninstrumented peers to support showing tunnel resource as summary span between actual resources based on address information in span properties, e.g. resource1 -> devtunnel -> resource2. Right now, even though the tunnel port resource has an endpoint with a URL that matches the URL the request goes to (resource1 -> devtunnel), it doesn't get picked up and shown as a peer.

Start by tracing the dashboard handling for uninstrumented peers and how it reads address information from span properties. Verify the existing endpoint matching behavior, then define completion as showing the tunnel resource as a summary span between the two actual resources, such as resource1 → devtunnel → resource2.

Written by the indexing model from the issue text.