Add getStats() to PCTransport

[rnakano]

We used to manually collect and analyze PeerConnection stats like this:

room.engine.publisher.pc.getStats();

However, this became unavailable with the changes in #903, So, we wanted to add a way to call getStats() as an alternative.

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🦋 Changeset detected

Latest commit: 82027e7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
livekit-client	Patch

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All committers have signed the CLA.

[lukasIO]

Thanks for the PR. Understand the requirement, just be aware that we're planning some more changes to internal modules in the coming weeks, so there might be additional changes you'll have to make in the near term future.

[rnakano]

Got it, and thanks for the review!