src: add --libdir to override buildin libdir

[mvo5]

src: add --libdir to override buildin libdir

This allows the local developer to easily run local externals. Similar
to the experience with osbuild and given that otk developers will
most likely also run osbuild having the two similar is probably
a good thing.

[draft as the this is only very lightly tested (and not lint happy)]

[supakeen]

Thank you, my only concern here is adding the local developer case by default to the search path.

[supakeen]

I'd support having a relative path but instead of magically inserting them have them behind a single argument flag like -d on the main command for dev?

[mvo5]

I'd support having a relative path but instead of magically inserting them have them behind a single argument flag like -d on the main command for dev?

I pushed a new version that adds --libdir in the spirit of osbuild, given that the two will often be used in parallel it's probably a good idea to keep them similar.

[supakeen]

The type checker needs appeasement then we can get it in. --libdir is fine to me. There's no real reason to have _libdir + libdir() property as we aren't doing anything to it right but that's so minor.

(also let's undraft).