[REQUEST]: Expose Unity.WebRTC class on RenderStramingInternal

[kannan-xiao4]

Is your feature request related to a problem?

RenderStreamingInternal class is the only place we found that uses PeerConnection and RTCDataChannel but it is pretty much abstracted. This feature is a way we can use Unity.WebRtc and Unity.RenderStreaming in pair.

e.g. We thought of sending aspect ratio of both devices to each other as a text message and synchronize the cursor position accordingly.

Describe the solution you'd like

expose com.unity.webrtc class on RenderstreamingInternal.

Describe alternatives you've considered

No response

Additional context

related conversation https://github.com/Unity-Technologies/UnityRenderStreaming/issues/454#issuecomment-1131405008

[kannan-xiao4]

memo: URS-447