Add support for plugin links (#6386)

Co-authored-by: Nerixyz <nerixdev@outlook.de>

src/controllers/plugins/api/Message.hpp

@@ -1,9 +1,12 @@
 #pragma once
 #ifdef CHATTERINO_HAVE_PLUGINS
+#    include "messages/Link.hpp"
 #    include "messages/Message.hpp"
 
 #    include <sol/forward.hpp>
 
+#    include <cstdint>
+
 namespace chatterino::lua::api::message {
 
 /* @lua-fragment
@@ -32,6 +35,7 @@ c2.Message = {}
 ---@class MessageElementInitBase
 ---@field tooltip? string Tooltip text
 ---@field trailing_space? boolean Whether to add a trailing space after the element (default: true)
+---@field link? c2.Link An action when clicking on this element. Mention and Link elements don't support this. They manage the link themselves.
 
 ---@alias MessageColor "text"|"link"|"system"|string A color for a text element - "text", "link", and "system" are special values that take the current theme into account
 
@@ -86,6 +90,20 @@ c2.Message = {}
 function c2.Message.new(init) end
 */
 
+/** @lua@alias c2.Link { type: c2.LinkType, value: string } A link on a message element. */
+
+// We only want certain links to be usable
+// Note: code dependant on this needs these values to be meaningful `Link::Type`s
+/** @exposeenum c2.LinkType */
+enum class ExposedLinkType : std::uint8_t {
+    Url = Link::Type::Url,
+    UserInfo = Link::Type::UserInfo,
+    UserAction = Link::Type::UserAction,  // run a command/send message
+    JumpToChannel = Link::Type::JumpToChannel,
+    CopyToClipboard = Link::Type::CopyToClipboard,
+    JumpToMessage = Link::Type::JumpToMessage,
+};
+
 /**
  * @includefile singletons/Fonts.hpp 
  * @includefile messages/MessageElement.hpp