Support the runtime as a dynamic / shared library (only)?

[bradcray]

In a few conversations recently, such as #26024 (comment), we've been discussing how Chapel libraries tend to have their own private copy of the runtime bundled in with them, such that if multiple libraries are used, or a Chapel library is used with a Chapel program, we end up with multiple copies of the runtime, each of which would like to own hardware resources (like pinning threads to cores).

This issue asks a question that's come up from time to time over the years: What would it take to structure our runtime as a dynamic / shared library that was loaded independently of any specific Chapel executable or library, such that if multiple things with a process needed the runtime, they'd all share that single library instance rather than each getting and initializing their own?

[bradcray]

@dlongnecke-cray : I filed this based on our conversation earlier this week

[mppf]

IMO the main challenge here is that the runtime uses the ftable (and probably a few other things that are code-generated tables / arrays) just by linking to it.