Copy links with CopyToClipboard instead of a popup

Clicking a chat URL and the GUI's Donate/GitHub/Website buttons now put the address straight on the clipboard and say so in chat. The url link goes through ClassicAPI's LinkUtil handler registry, so SetItemRef is no longer replaced. Exporting a profile also copies the string.

env/translations_zhCN.lua

@@ -161,6 +161,7 @@ pfUI_translation["zhCN"] = {
   ["Cooldown Text Time Threshold"] = "技能冷却时间文字临界值",
   ["Coordinates Location"] = "坐标位置",
   ["Coordinates On Minimap"] = "小地图上的坐标",
+  ["Copied to clipboard"] = nil,
   ["Count"] = "计数器",
   ["Create Profile"] = "新建配置",
   ["Ctrl-Click"] = "CTRL点击",