Generate a local post from logs

[AngeloStavrow]

As a way to help with troubleshooting, provide a way for users to pull the logs from OSLogStore and drop them into a new local post, which can be e.g. uploaded as an anonymous post to share with developers for troubleshooting.

Bonus points if we prompt the user to generate such a "log post" after a crash is detected.

⚠️ Note that OSLogStore is only available on iOS 15 or later, so this feature won't be available to users that stay on iOS 14. Anyone that can run iOS 14 should be able to also run iOS 15, so that isn't a blocker.