[Core][Distributed] Use IPC (domain socket) ZMQ socket for local comms

[njhill]

Should be more efficient than TCP based

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[youkaichao]

the change looks good to me. do you have any performance numbers?

[njhill]

the change looks good to me. do you have any performance numbers?

@youkaichao no, I'm actually not sure how often this queue is used, it just seemed that it would make most sense to use the local transport for the local queue.

[youkaichao]

for local communication, we usually use shared memory. this zmq socket is a backup plan when the message size is too large.

[njhill]

Understood, but it's still local-only right? so might as well use the local transport?

[njhill]

(remaining test failure was also failing on main I think)

[youkaichao]

LGTM