Improve server web socket performance.

[kamilkloch]

Tapir layer for web sockets adds a considerable overhead, when compared to raw http4s + blaze:

http4s + blaze:

#[Mean    =        0.025, StdDeviation   =        0.157]
#[Max     =        3.000, Total count    =      6000000]

tapir + blaze:

#[Mean    =       41.509, StdDeviation   =       57.180]
#[Max     =      748.000, Total count    =      6000000]

Repo with benchmark: https://github.com/kamilkloch/websocket-benchmark/tree/master/results

[kciesielski]

@kamilkloch thanks a lot for testing the performance overhead and sharing test sources + results! We are now starting to work on extending our perf tests. Is it OK if we use your code in our tests, of course with proper attribution?

[kamilkloch]

Sure thing. That is also work of @plokhotnyuk.
The repo is currently not quite up-to-date, we were planning to re-run the benchmarks once the new tapir has landed ;)