add full-stack rama benchmarks

[GlenDC]

Within https://github.com/plabayo/rama/tree/main/benches it would be good to have a couple of benchmarks, also driven by divan, for:

h1 (over tcp):

• client <-> server
• client <-> proxy <-> server

h2 (over tcp):

• client <-> server
• client <-> proxy <-> server

Use a realistic amount of layers as well, to make sure we get a good idea full stack.

This probably would be enough to resolve #340,
as it would allow us to track overtime how we are doing performance and allocation wise.

Bonus points if you can figure out how to get some nice summary tables out of these benchmarks so we can have them visible somewhere, but even better if we can make it part of the CI + PR check. This is however to be done perhaps as a separate ticket/PR, so first focus on just having the missing e2e benchmarks.