v2.0 Adding `add ci.tbl summary()`

[ddsjoberg]

• This is on hold add_stat() is added.

• @zdz2101 I think you looked into this during the development of cardx's proportion functions. Methods c("exact", "asymptotic") are calculated with Hmisc::binconf(). Do these correspond to methods we've implemented in cardx?

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Reviewer Checklist (if item does not apply, mark is as complete)

• [ ] Ensure all package dependencies are installed by running renv::install()
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