fix(core): max event listeners error long running process

[andrewdoro]

Fixes #7963

We are seeing this error on prod at Anara.
We are using Vercel Fluid compute to optimize serverless execution.

This results in long running processes. The addEventListener is not being cleaned up when doing multiple executions.

This error also happened a year ago. Implemented a similar fix.
#6461

adds an abort listener to the passed options.signal, but never removes it manually.

When Runnable.stream() or streamEvents() is called repeatedly with the same signal (or multiple times in parallel), the listeners accumulate, eventually triggering:

(node:75561) MaxListenersExceededWarning: Possible EventTarget memory leak detected. 11 abort listeners added to [AbortSignal]. MaxListeners is 10. Use events.setMaxListeners() to increase limit
(Use node --trace-warnings ... to show where the warning was created)
In long-running apps or with multiple concurrent streams, this can become problematic.

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[hntrl]

@andrewdoro I'm fine to merge this since it's technically correct listener handling, but I'm not convinced this solves your issue. This error shouldn't be emitted because 10 or more identical event listeners were added in global space but because 10 or more were added to a single signal. Is this happening on the first streamEvents call or in subsequent calls? Are you sharing a single abort signal w/ a lot of items? (assuming this is part of a StateGraph) Do you have a lot of subgraphs?

Have you been able to test this in Vercel? If not, can you get the same error to produce when using a local node environment?