Metrics for downloads - B2AI Voice

[satra]

we would like to be able to download metrics (over some period). here are some, i'll let @alistairewj chime in with anything else:

• number of registrations
• number of downloads (by version)
• institutions of the registrants

if a download button is available for project contributors/owners that would be sufficient for the time being. these could be cumulative metrics or per period (e.g., month).