Pack has been published to the Pack Gallery! See the listing here:
Also, if anyone finds themselves building a simple doc that showcases some of the functionality of the pack, please consider sharing it so that it can appear on the Pack listing and demonstrate its usage for other Coda users!
(The below workaround is no longer needed now that the pack is verified)
Note that after adding the pack to your doc, you will need to connect a Google account.
Since the pack uses Google APIs to access Google users’ data, it must undergo a verification process before being properly published. At the moment, it is published but unverified. This means that you can connect your Google account, but Google will display a scary “Unverified app” screen before displaying the usual OAuth consent screen. You can read more about it here: https://support.google.com/cloud/answer/7454865
There is no good way yet as a Pack developer to verify Coda Pack with Google, so the workaround is to click on the “Advanced” link in the “Unverified app” screen, and then on the “Go to coda.io (unsafe)” link. See images below.
Coda has put in place fairly extensive measures to prevent bad actors from mishandling your data associated with 3rd party services (e.g. your Google account), but for peace of mind I have made the source code open source (even though there is no way of knowing whether that code is indeed what was used to build the pack 
).