Add namespaces to mirrord ls output

[Razz4780]

Issue #2999

Since mirrord ls currently returns a list of target paths, it was not possible to implement this without adding an extra env. IDEs will have to inspect mirrord binary version or try parsing the new format with fallback to the old one.

Additionally, fixed mirrord::port_forward module visibility and removed some dead code.

[meowjesty]

Some nits here and there.

The main thing is, I would prefer to have kube interactions under the kube resource struct, as I find it's easier to think about (my thought process is usually: I want kube stuff, create this struct, now it offers me an api with exactly what I want ... Oh it doesn't have what I want? I add it to the struct). But we never talked about api design (not that I remember), maybe we should bring this up to the team?

[meowjesty]

And here you prefer present for all the docs. I feel trolled.

🧌