Part of the way we want to alert clients that a message has been pinned / unpinned is by introducing a new message type and message spec to represent toggling a pin. I've decided to consolidate the two actions into one spec and handle the robotext / notif texts that are sent within the functions to avoid lots of duplicate code (much like update-relationship-message-spec.js). We could probably indicate a message preview like 'you pinned "This is a message to b..."', but if we want to do that I'd prefer to handle that in a later diff once the core keyserver implementation is done.
Depends on D7112
Linear: https://linear.app/comm/issue/ENG-3190/introduce-a-new-message-type-and-spec-for-toggling-pins