Allow ConvexHttpClient in withArgs

[thomasballinger]

As a future direction how about withArgs can return more full wrappers of various clients? If that works as a plan then it's fine to add more clients here and a type parameter for the client type in the future, but for now it's just the same interface!

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[ianmacartney]

If you mean having them implement more of the interface, yes sgtm - I was wondering if this is the right spot for a proxy object approach.

If what you mean by full client is that this does the initialization too, then I'm not sure.
For stateful clients, I suspect there will be a lot of hybrid calls with and without extra params. And I suspect this one could be nested too to have e.g. one that supplies an apiKey argument, and another elsewhere that adds a userId argument?

[thomasballinger]

Proxy or manually passing through the supported methods/properties sounds good, makes sense that these should be lightweight wrappers so you can create many.