feat: Enable Markdown Parsing in emails (#1663)

Co-authored-by: Pranav Raj S <pranav@chatwoot.com>

app/views/mailers/conversation_reply_mailer/conversation_transcript.html.erb

@@ -1,3 +1,4 @@
+<% markdown = Redcarpet::Markdown.new(Redcarpet::Render::HTML, autolink: true, tables: true) %>
 <% @messages.each do |message| %>
   <tr>
     <td>
@@ -7,7 +8,7 @@
   <tr>
     <td style="padding-bottom: 16px;">
       <% if message.content %>
-        <%= message.content %>
+        <%= markdown.render(message.content).html_safe %>
       <% end %>
       <% if message.attachments %>
         <% message.attachments.each do |attachment| %>

app/views/mailers/conversation_reply_mailer/reply_with_summary.html.erb

@@ -1,3 +1,4 @@
+<% markdown = Redcarpet::Markdown.new(Redcarpet::Render::HTML, autolink: true, tables: true) %>
 <p>Hi <%= @contact.name %>,</p>
 
 <p>You have new messages on your conversation.</p>
@@ -11,7 +12,7 @@
   <tr>
     <td style="padding: 10px 20px; margin: 5px 0 20px 0; background: #F2F3F7; border-radius: 10px; display: inline-block; font-family: "Helvetica Neue",Tahoma,Arial,sans-serif; text-align: start; unicode-bidi: plaintext;">
       <% if message.content %>
-        <%= message.content %>
+        <%= markdown.render(message.content).html_safe %>
       <% end %>
       <% if message.attachments %>
         <% message.attachments.each do |attachment| %>

app/views/mailers/conversation_reply_mailer/reply_without_summary.html.erb

@@ -1,7 +1,9 @@
+<% markdown = Redcarpet::Markdown.new(Redcarpet::Render::HTML, autolink: true, tables: true) %>
+
 <% @messages.each do |message| %>
   <p style="font-family: Roboto,"Helvetica Neue",Tahoma,Arial,sans-serif; text-align: start; unicode-bidi: plaintext;">
     <% if message.content %>
-      <%= message.content.gsub("\n", "<br/>").html_safe %>
+      <%= markdown.render(message.content).html_safe %>
     <% end %>
     <% if message.attachments %>
       <% message.attachments.each do |attachment| %>