build: add initial meson support

[brenfwd]

This PR adds initial support for the meson build system. Currently set up to work as a shared/static library, since that works best with meson's dependency system for libuv.

This should be able to be backported to the current release as well if desired.

[skypjack]

Maybe it's worth it to add a note to the build instructions here?
Otherwise, please drop a few lines in a comment and I can add them to the readme file. I think we should to the same with vcpkg anyway.

[brenfwd]

Updated build instructions, lmk what you think :)

[skypjack]

@stefanofiorentino any concerns? I'm about to merge this one otherwise.

[brenfwd]

@skypjack @stefanofiorentino good to merge?

[skypjack]

Actually, I don't have enough knowledge to say if it's good to merge for the meson part.
I'm fine with merging it but I won't be able to maintain it in the long run because I'm not into meson.
I'm sorry. Is there any way to test it on the CI and have red flag in case of failure?

[skypjack]

Ping @brenfwd ☝️

[brenfwd]

I believe this should do the trick.

https://github.com/brenfwd/uvw/actions/runs/7817930848/job/21326979681

[brenfwd]

(renamed commit msg)

[skypjack]

Meson support is broken. As anticipated, I don't have enough knowledge nor bandwidth to maintain it.
@brenfwd are you willing to help with it? I'm afraid I'll have to drop it otherwise. Please, let me know. Thanks.

[brenfwd]

@skypjack Sure thing, will look into it and PR a fix