Ian/threads no order

[ianmacartney]

@convex-dev/agent@0.0.5-alpha.1 has made each agent-as-tool into its own thread, setting the parent thread id for later
It now also doesn't have a specific order for threads, just uses creation time.
Using order and subOrder on messages might be a similar footgun, we'll see if those go away too

Fixes #13

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[ianmacartney]

Also this fixes the issue where when passed recentMessages=0 it was still fetching one document (filed get-convex/convex-helpers#534)