Make release workflow more robust

[fvictorio]

When publishing 0.3.6, we had an issue where one of the builds wasn't published. The underlying reason was that the meaning of macos-latest as an OS value changed since the last release. This was fixed in #415, but we should make some deeper changes to prevent this from happening again.

At the very least, we should add a step that checks that all the crates/edr_napi/npm directories have a .node file, or fail otherwise. But there might be other things we can do instead or in addition to this.

[Xanewok]

While we some some involved infrastructure in Slang, we also happen to do the check for that (and instrument the napi build a bit more ourselves) in https://github.com/NomicFoundation/slang/blob/3845dc78da4a29eccaa3193417ffd9506fab697d/crates/infra/cli/src/toolchains/napi/cli.rs#L88-L92.

Not saying we should do the same but maybe there is some helpful logic that we could carry over here.