most of the code was moved to the transcoder layer.
The `compression_threshold_size` option has been removed.
The `:compression/brotli` plugin becomes only ´:brotli`, and depends on
the new transcoding APIs.
options to skip compression and decompression were added.
These internnal registries were a bit magical to use, difficult to
debug, not thread-safe, and overall a nuisance when it came to type
checking. So long.
The reference for a request verb is now the string which is used
everywhere else, instead of the symbol corresponding to it. This was an
artifact from the import from httprb, and there is no advantage in it,
since these strings are frozen in most use cases, and the
transformations from symbol to strings being performed everywhere are
prooof that keeping the atom isn't really bringing any benefit.
there was a long-standing buggy workaround, whereas in stream-mode, when
there was no response yet to query from, a synchronous request would be
fired. This would break when under event streams, so we had to document
this as "make sure that...".
This fixes it by implementing a general session API convention, which
separates the step of sending the requests, from waiting for its
receival. And, given that the request knows when the response is
available, we can actually "tick until response".
This might be used in the future to refactor the way we handle the
responses, which buffer the full payload by default, instead of reading
from the connection at will.
