The main change needed to make `piker.data.feed._FeedsBus` work was
to correctly format the `'trade'` msgs with the (new schema) expected
`'ticks': list[dict]` field which,
- we compute the `piker` quote-msg-`dict` from the (now directly proxied through)
`cryptofeed.types.Trade`'s fields inside the body of `stream_quotes()`.
- similarly, move the `'l1'` msg processing, **out of** the `asyncio`-side
`_l1()` callback (defined as a closure in `.api.aio_price_feed_relay()`
and passed to the `cryptofeed.FeedHandler`) and instead mod the
callback to simply pass through the `.types.L1Book` ref directly to
the `piker`/`trio` side task for conversion.
In support of all that,
- mask-to-drop the alt-branch to wait on a first rt event when the
`cryptofeed.LastTradesResult.trades: list[Trade]` is empty; doesn't
seem like this ever even happens?
- add a buncha typing, comments and doc-strs to the routines in
`.deribit.api` including notes on where we can choose to mod the
`.bs_fqme` for our eventually preferred `piker` style format.
- simplify some nested `@acm` enters to the new single `async with
<tuple>)` style.
- be particularly pedantic about typing
`tractor.to_asyncio.LinkedTaskChannel`
- bit of pep8 line-spacing fixes in `.venues`.