Bookmarking a kind 34550 community now writes to the NIP-51 Communities
list (kind 10004) keyed by the addressable coordinate, so the reference
stays valid across community updates. My Communities merges bookmarked
communities as a third discovery source alongside founded and member-of,
with Founder/Member/Bookmarked badges on each card.
Bookmark toasts live on the mutation itself so they survive the more-menu
dialog unmounting between .mutate() and publish resolution.
lemon