feat: add confirm step to message-level delete

Clicking del now shows 'confirm delete / cancel' inline in the action
bar. Cancel rebuilds the original buttons; confirm proceeds as before.
Matches the session delete pattern added in the prior commit.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cortex/static/app.js

@@ -935,7 +935,20 @@
             delBtn.className = 'msg-act-btn del';
             delBtn.innerHTML = icon_html('trash-2', 12) + ' del';
             delBtn.addEventListener('click', () => {
-                deleteMsg(wrapper);
+                actionsDiv.innerHTML = '';
+
+                const yesBtn = document.createElement('button');
+                yesBtn.className   = 'msg-act-btn del';
+                yesBtn.textContent = 'confirm delete';
+                yesBtn.addEventListener('click', () => deleteMsg(wrapper));
+
+                const noBtn = document.createElement('button');
+                noBtn.className   = 'msg-act-btn';
+                noBtn.textContent = 'cancel';
+                noBtn.addEventListener('click', () =>
+                    attachHistoryControls(msgDiv, parseInt(wrapper.dataset.histIdx)));
+
+                actionsDiv.append(yesBtn, noBtn);
             });
 
             actionsDiv.appendChild(editBtn);

documentation/TODO__Agents.md

@@ -139,7 +139,7 @@ ability to act on HA via the REST API.
 
 ### [UX] Session delete confirmation
 - [x] Inline "Delete this session? [Delete] [Cancel]" reveal on `×` click in `app.js` — 2026-05-12
-- [ ] Consider: also confirm for message-level delete (Edit/Delete hover controls)
+- [x] Message-level delete: "confirm delete / cancel" inline in the actions bar — 2026-05-12
 
 ### [UI] File attachments in chat
 Upload an image or document inline and have it flow into context. Natural workflow