Lack of documentation for genericServerT prevents its correct use and its understanding

[Kleidukos]

To this day, genericServerT suffers from a lack of documentation, explanation of its differences from genericServer, and example usages.

This being combined to the rather obtuse type signatures one can find in Servant codebases, Haskell developers who are new to the framework or even to codebases using it are easily lost.

cc @alpmestan

[phadej]

genericServer  :: GenericServant routes  AsServer     => routes  AsServer     -> ToServant routes  AsServer
genericServerT :: GenericServant routes (AsServerT m) => routes (AsServerT m) -> ToServant routes (AsServerT m)

I don't really know what one could write about genericServerT except the

Transform record of endpoints into a ServerT m.

Where genericServer is documented as

Transform record of endpoints into a Server.

---

An example usage is in https://docs.servant.dev/en/stable/cookbook/generic/Generic.html#using-generics-together-with-a-custom-monad

[Kleidukos]

@phadej It may be not much but still significantly better than nothing. :)
Linking or including the example usage would be quite an improvement as well.
Do you wish me to make a PR in that direction?

[phadej]

I really have no opinion, if you think you know how to improve the docs, please make a PR.

[Kleidukos]

Closed by #1279