I'm also interested in learning about why the API keys are required to build.
I made it required to prevent accidentally ship app without any analytics/error tracking. (analytics can be opted out)
For ex, https://github.com/fastrepl/hyprnote/blob/327ef376c1091d093c...
EDIT: Prod -> release
Given your target market, have you considered looking at Bugsink?[0] sentry compatible. still not local, but at least you won't have to additionally ask your customers to trust sentry/posthog.
Disclosure: that's me