fix: tid set to null

[XavierChanth]

fixes #1524

The problem:

• If the first thread for srv is created, but the second one fails, then the thread_id for joined thread is not set.

- What I did

• I reverted my changes setting tid to NULL, which didn't actually fix the problem, this was a one-off in a bulk of changes to struct initializers.
• I instead added a boolean value which, if the second thread fails to create, skips checking which thread tid is. It instead triggers the cancel for the first thread, since we know the first thread is the open one at this point.

- How I did it

- How to verify it

- Description for the changelog
fix: tid set to null

[XavierChanth]

@cpswan do I need to update version? We have no binaries uploaded for 0.2.4,
so I think we can re-release under that?

[cpswan]

@XavierChanth if you think this fixes #1524 then I'm happy for c0.2.4 to be re-released - so no need to bump

[XavierChanth]

Waiting for e2e tests as a preliminary sanity check