Add/Show/Delete Emojis on Notes (#181)

This MR adds the ability to view, add, and delete emojis from notes and comments.

This action can be performed by default with the `Ea` (emoji add) keybinding, and the `Ed` (emoji delete) keybinding. Only emojis added by the current user are eligible for deletion. The MR also implements a popup functionality which shows the user who added emojis on hover.

Implements #179

lua/gitlab/actions/discussions/annotations.lua

@@ -66,6 +66,18 @@
 ---@field discussions Discussion[]
 ---@field unlinked_discussions UnlinkedDiscussion[]
 
+---@class EmojiMap: table<string, Emoji>
+---@class Emoji
+---@field	unicode           string
+---@field	unicodeAlternates string[]
+---@field	name              string
+---@field	shortname         string
+---@field	category          string
+---@field	aliases           string[]
+---@field	aliasesASCII      string[]
+---@field	keywords          string[]
+---@field	moji              string
+
 ---@class WinbarTable
 ---@field name string
 ---@field resolvable_discussions number