epic: expose transport metrics

Nobody has claimed this yet.

## Done Criteria

1. Export metrics leveraging the work done in https://github.com/libp2p/js-libp2p/issues/1458
2. Transport metrics, similar to those already created for TCP, are emitted for all js-libp2p transports

## Motivation

Epic created since we only had one tracking the work from https://github.com/libp2p/js-libp2p/issues/1915

Better observability for performance and benchmarking. See: https://github.com/libp2p/js-libp2p/issues/1458#issuecomment-1323833476

## Questions

- [ ] Do we want to add metrics to `packages/transport-circuit-relay-v2`?

## Related

* https://github.com/libp2p/js-libp2p/issues/1915
* https://github.com/libp2p/js-libp2p/pull/2649#discussion_r1716665370
* https://github.com/libp2p/js-libp2p/issues/2077
* https://github.com/libp2p/js-libp2p/issues/2080
* https://github.com/libp2p/js-libp2p/issues/2099

```[tasklist]
### Tasks
- [ ] https://github.com/libp2p/js-libp2p/issues/1915
- [ ] feat: expose metrics for WebTransport
- [ ] feat: expose metrics for WebRTC
- [ ] feat: expose metrics for maconn upgrades in @libp2p/upgrader (part of `libp2p` npm package: https://github.com/libp2p/js-libp2p/blob/7939dbd5cbab1c7b4be671ff976d0258e9b48178/packages/libp2p/src/upgrader.ts#L126C36-L126C52)
```

Start by reviewing issue 1915 and the existing TCP transport metrics work. Then inspect packages/libp2p/src/upgrader.ts at the linked entry point and the transport packages named in the task list, including WebTransport, WebRTC, and packages/transport-circuit-relay-v2. Done means metrics are exposed for the agreed transports and the open task list is resolved.

Written by the indexing model from the issue text.