introduced notificationTexts function to reaction message spec. Keeping the notification text generic for now with "user liked a message" and "user unlike a message", but will put up a follow up task to further improve the notification text because what I mention below is a bit out of the scope for the first version of message liking
- Only send a notification if the user adds a like/reaction
- Rescind a reaction notif and don't show anything new if the user removes a like/reaction
- only the user who sent the target message gets a notification