Crate is no longer releaseable

[sprudel]

Since merge of #593 the crate has been split into two crates publishing pipeline has not been adapted.
So since then the publishing of the zitadel crate was broken. It is unclear to me if this was an intentional change.

A decision has to be made:

a) keep the split but also publish the zitadel-gen crate
b) unify into one crate again

Or do we have alternatives?

Regarding option a) it is unclear to me if the versioning scheme for zitadel_gen crate is correct. It tries to reflect the version of the underlying api, but there also other components (prost tonic) which might need an update.

[sprudel]

@fcenedes, @buehler do you have input here?

[sprudel]

Comparing with the approach of k8s-openapi crate, it seems using feature flags is the better approach for versioning of the API, compare https://github.com/Arnavion/k8s-openapi/blob/master/Cargo.toml

[buehler]

Regarding the way on how to "version" the API, I do not have strong opinions. Never encountered this issue before :)
Both ways would be fine for me. But since the workload is smaller with b) I'd favor b and let the generated code be part of the initial crate again.
I don't see much value in deploying two crates.

[sprudel]

In principle, I think the decoupling into different crates is the correct pattern in Rust's eco system, but I feel we should do this with more consideration.

For now I suggest we go back to the initial state of one crate and separated later into a different ones.

[sprudel]

So I prepared a pr to revert the split
#618