Correctly accept, aggregate, and expose reactions.
Fixes #304
This allows for a single user to have and manage multiple reactions, although I don't know if Misskey/etc agree with that. (This is like Slack and Discord but unlike Telegram and Facebook.) [The Iceshrimp UI suggests it only supports one reaction per user per post.]
(And I know this feature is borderline useless under the current ecosystem. Honestly, this is more for me than for the community--it seemed like a good introductory issue, and I really like reactions in things.)
Correctly accept, aggregate, and expose reactions.
Fixes #304
This allows for a single user to have and manage multiple reactions, although I don't know if Misskey/etc agree with that. (This is like Slack and Discord but unlike Telegram and Facebook.) [The Iceshrimp UI suggests it only supports one reaction per user per post.]