Development setup for changes effecting API + SDK/Plugins

[Flarna]

• [x] This only affects the JavaScript OpenTelemetry library
• [ ] This may affect other libraries, but I would like to get opinions here first

The development setup for plugins in contrib repo was already quite cumbersome if you want to adapt something to match changes done in core repo before an actual release of core was done.

But now we have even one more indirection as API was moved into a new repo.

Is there a known "easy" setup if someone has the need to add a new API and wants to use it in a plugin hosted in contrib? I have not tried yet but I fear that the dependencies to packages here - which in turn depend on API - easily result in having two (incompatible) versions of API installed.

I think some (nightly) CI setup to verify that tip latest API main works with latest core main would be nice. One step further would be a CI run to verify latest contrib + latest core + latest API.