This commit fixes a crash that occurred when clicking "follow all"
during onboarding.
This fix works by making `Contacts` and `PostBox` isolated into a
specific Swift Actor, and updating direct and indirect usages
accordingly.
Changelog-Fixed: Fixed a crash that occurred when clicking "follow all" during onboarding.
Closes: https://github.com/damus-io/damus/issues/3422
Co-authored-by: alltheseas <64376233+alltheseas@users.noreply.github.com>
Signed-off-by: Daniel D’Aquino <daniel@daquino.me>
