Add resend message button

Messages now include another "upstream" button next to the main archive
icon: a link that immediately goes to the resend message page.

Author: dutow

app/assets/stylesheets/components/messages.css

@@ -125,6 +125,10 @@
     display: inline-flex;
     align-items: center;
   }
+
+  & a + a {
+    margin-left: var(--spacing-2);
+  }
 }
 
 .message-content {

app/views/topics/_message.html.slim

@@ -47,6 +47,8 @@
         .message-archive-link
           = link_to "https://postgr.es/m/#{ERB::Util.url_encode(message.message_id)}", target: "_blank", rel: "noopener", data: { turbo: false }, title: "View on postgr.es", "aria-label": "View on postgr.es" do
             i.fa-solid.fa-building-columns
+          = link_to "http://www.postgresql.org/message-id/resend/#{ERB::Util.url_encode(message.message_id)}", target: "_blank", rel: "noopener", data: { turbo: false }, title: "Resend from postgresql.org archive", "aria-label": "Resend from postgresql.org archive" do
+            i.fa-solid.fa-paper-plane
 
   .message-content class=read_classes.join(" ") data=read_data
     - if message.subject != @topic.title && message.subject.present?