ref(replays): Clean up RRWeb event parsing logic (#93517)

As we mess around with extracting data from RRWeb we need more robust
methods of handling the data. The previous code was adhoc and was
breakable given a sufficiently motivated person wanted to break it. It
didn't break because the SDK has a limited range of event-formats it
provides but that does not imply that no one could send bad events in
the future.

We naively parse the events and if parsing fails we handled the
exception.

---------

Co-authored-by: Andrew Liu <[email protected]>

Author: cmanallen