feat: add release reactions and a GitHub-like reaction bar (#38415)

Adds emoji reactions to releases and moves the reaction picker of
issues, comments and releases into a GitHub-like reaction bar.

- Releases omit 👎 or 😕
- Drafts and tags can't be reacted to
- Moved menu to tippy
- Added keyboard navigation

Fixes: https://github.com/go-gitea/gitea/issues/34268
Fixes: https://github.com/go-gitea/gitea/issues/16676
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

custom/conf/app.example.ini

@@ -1434,11 +1434,14 @@ LEVEL = Info
 ;; The icon theme for folders (basic/material)
 ;FOLDER_ICON_THEME = basic
 ;;
-;; All available reactions users can choose on issues/prs and comments.
+;; All available reactions users can choose on issues, pull requests and comments.
 ;; Values can be emoji alias (:smile:) or a unicode emoji.
 ;; For custom reactions, add a tightly cropped square image to public/assets/img/emoji/reaction_name.png
 ;REACTIONS = +1, -1, laugh, hooray, confused, heart, rocket, eyes
 ;;
+;; Reactions available for releases
+;;RELEASE_REACTIONS = +1, laugh, hooray, heart, rocket, eyes
+;;
 ;; Change the number of users that are displayed in reactions tooltip (triggered by mouse hover).
 ;REACTION_MAX_USER_NUM = 10
 ;;