Add error message copy button

internal/service/static/render.js

@@ -407,6 +407,7 @@ export class Renderer {
     const $msg =
       this.$tplErrorMessage.content.cloneNode(true).firstElementChild;
     $msg.querySelector('.message__content').textContent = message;
+    $msg.dataset.copyText = message;
     this.$chat.insertBefore($msg, this.$chatLoading);
     this.scrollToBottom();
   }

internal/service/templates/static/templates.gohtml

@@ -118,6 +118,14 @@
         <div class="message__actions">
           <svg class="message__icon" aria-hidden="true"><use href="/static/icons.svg#assistant"></use></svg>
           <div class="message__actions-buttons">
+            <button
+              type="button"
+              class="message__action-btn"
+              data-action="copy"
+              aria-label="Copy to clipboard"
+            >
+              <svg class="icon"><use href="/static/icons.svg#copy"></use></svg>
+            </button>
             <button
               type="button"
               class="message__action-btn message__action-btn--delete"