Add a copy button for the Lightning address

Same as on profile settings page.

app/views/services/lightning/index.html.erb

@@ -7,13 +7,25 @@
 
   <section>
     <h3>Lightning Address</h3>
-    <p>
+    <p class="mb-6">
       Your Kosmos user address is also a
       <a class="ks-text-link" href="https://lightningaddress.com/" target="_blank">Lightning Address</a>!
       The easiest way to receive sats is by just giving out your address:
     </p>
-    <p>
+    <p data-controller="clipboard" class="flex gap-1 sm:w-2/5">
-      <strong><%= current_user.address %></strong>
+      <input type="text" id="user_address" class="grow"
+             value=<%= current_user.address %> disabled="disabled"
+             data-clipboard-target="source" />
+      <button id="copy-user-address" class="btn-md btn-icon btn-blue shrink-0"
+              data-clipboard-target="trigger" data-action="clipboard#copy"
+              title="Copy to clipboard">
+        <span class="content-initial">
+          <%= render partial: "icons/copy", locals: { custom_class: "text-white h-4 w-4 inline" } %>
+        </span>
+        <span class="content-active hidden">
+          <%= render partial: "icons/check", locals: { custom_class: "text-white h-4 w-4 inline" } %>
+        </span>
+      </button>
     </p>
   </section>