This gets the binance provider meeting the data feed schema requirements
of both the OHLC sampling/charting machinery as well as proper
formatting of historical OHLC history.
Notably,
- spec a minimal ohlc dtype based on the kline endpoint
- use a dataclass to parse out OHLC bar datums and pack into np.ndarray/shm
- add the ``aggTrade`` endpoint to get last clearing (traded) prices,
validate with ``pydantic`` and then normalize these into our tick-quote
format for delivery over the feed stream api.
- a notable requirement is that the "first" quote from the feed must
contain a 'last` field so the clearing system can start up correctly.