Add slug to campaign API

[NicoHood]

Is your feature request related to a problem? Please describe.
I am writing and updating listmonk newsletters through the api. What is currently hard for me is to identify existing campaigns. I'd need to either note the id when I first uploaded them or I need to check the name/subject, which is a human but not so good machine readable name.

Describe the solution you'd like
I'd like to have an id by name, maybe a slug. This special-campaign-name can be translated from the Human readable name (or better Special Campaign Name).

Maybe this slug could also be used for the public archive page feature:
#540

What do you think?

[knadh]

The campaign name can be used as a slug as the subject line is what's shown to the outside world. There are also campaign tags (which cannot be queried via the API right now, but could be added).

[NicoHood]

Yeah, I also found my solution not fully thought out. Having tags in the API would be nice!