Do not use JSON for internal routing

[jmillan]

JSON encoding/decoding is very CPU intensive.

Use character separated string for internal routing representation.

data info from node to worker for Channel remains being JSON. data info from node to worker for PayloadChannel is a now string to be decoded by the target:

• At this moment only DataChannel ppid is used as data, and we are NOT sending it as JSON but as plain string.

[jmillan]

Canceling Rust GH actions because that changes are missing.

[Hartigan]

What you think about replacing json by protobuf? This way we can save CPU/RAM and generate types for typescript/c++/rust.

[jmillan]

We are completely removing any data structure for internal.

Data structures for data will be reviewed afterwards.

[ibc]

Closing in favor of https://github.com/versatica/mediasoup/pull/893