This adds a dummy v8-poc project that in Cargo links against our
prebuilt binaries and the ones provided by rusty_v8 for non musl
platforms. This demonstrates that we can successfully link and use v8 on
all platforms that we want to target.
In bazel things are slightly more complicated. Since the libraries as
published have libc++ linked in already we end up with a lot of double
linked symbols if we try to use them in bazel land. Instead we fall back
to building rusty_v8 and v8 from source (cached of course) on the
platforms we ship to.
There is likely some compatibility drift in the windows bazel builder
that we'll need to reconcile before we can re-enable them. I'm happy to
be on the hook to unwind that.
Alternative approach, we use rusty_v8 for all platforms that its
predefined, but lets build from source a musl v8 version with bazel for
x86 and aarch64 only. We would need to release this on github and then
use the release.
