fix: render slack emoji shortcodes as unicode characters (#12928)

This PR fixes an issue where Slack emojis are rendered as text
shortcodes (e.g. 🚀) instead of the actual emoji characters in
Chatwoot messages.

It introduces a new EmojiFormatter class that uses the emoji-data
mapping to convert shortcodes to unicode characters.

---------

Co-authored-by: Sony Mathew <sony@chatwoot.com>
Co-authored-by: Sony Mathew <2040199+sony-mathew@users.noreply.github.com>

lib/integrations/slack/emoji_formatter.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+class Integrations::Slack::EmojiFormatter
+  def self.format(text)
+    return text if text.blank?
+
+    text.gsub(/:([a-zA-Z0-9_+-]+):/) do |match|
+      short_code = Regexp.last_match(1)
+      # gemoji exposes find_by_alias; Rails/DynamicFindBy is a false positive because Emoji is not an ActiveRecord model.
+      # rubocop:disable Rails/DynamicFindBy
+      emoji = Emoji.find_by_alias(short_code)
+      # rubocop:enable Rails/DynamicFindBy
+      emoji ? emoji.raw : match
+    end
+  end
+end

lib/integrations/slack/slack_message_helper.rb

@@ -35,7 +35,7 @@ module Integrations::Slack::SlackMessageHelper
       message_type: :outgoing,
       account_id: conversation.account_id,
       inbox_id: conversation.inbox_id,
-      content: Slack::Messages::Formatting.unescape(params[:event][:text] || ''),
+      content: formatted_message_content,
       external_source_id_slack: params[:event][:ts],
       private: private_note?,
       sender: resolved_sender,
@@ -104,6 +104,11 @@ module Integrations::Slack::SlackMessageHelper
     [nil, nil, nil]
   end
 
+  def formatted_message_content
+    text = Slack::Messages::Formatting.unescape(params[:event][:text] || '')
+    Integrations::Slack::EmojiFormatter.format(text)
+  end
+
   def private_note?
     params[:event][:text].strip.downcase.starts_with?('note:', 'private:')
   end