Add admin user rename

static/js/admin.js

@@ -53,6 +53,7 @@ async function loadUsers() {
           </div>
         </div>
         <div style="display:flex;gap:8px;align-items:center;">
+          <button class="admin-btn-sm" data-adm-rename-user="${esc(u.username)}" style="font-size:11px;">Rename</button>
           ${u.is_admin ? '' : `<button class="admin-btn-delete" data-adm-del-user="${esc(u.username)}" style="font-size:11px;">Remove</button>`}
           ${u.is_admin ? '' : '<svg class="admin-user-chevron" width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round" style="opacity:0.3;transition:transform 0.2s,opacity 0.2s;"><polyline points="6 9 12 15 18 9"/></svg>'}
         </div>
@@ -106,7 +107,7 @@ async function loadUsers() {
         // Toggle panel visibility + rotate chevron + load models
         let _modelsLoaded = false;
         header.addEventListener('click', (e) => {
-          if (e.target.closest('.admin-btn-delete')) return;
+          if (e.target.closest('.admin-btn-delete, [data-adm-rename-user]')) return;
           privPanel.classList.toggle('hidden');
           const chevron = header.querySelector('.admin-user-chevron');
           if (chevron) {
@@ -143,6 +144,42 @@ async function loadUsers() {
         });
       }
 
+      // Rename button
+      const renameBtn = row.querySelector('[data-adm-rename-user]');
+      if (renameBtn) {
+        renameBtn.addEventListener('click', async (e) => {
+          e.stopPropagation();
+          const oldUsername = renameBtn.dataset.admRenameUser;
+          const next = await uiModule.styledPrompt(`Rename "${oldUsername}"`, {
+            defaultValue: oldUsername,
+            placeholder: 'New username',
+            confirmText: 'Rename',
+          });
+          const username = (next || '').trim();
+          if (!username || username === oldUsername) return;
+          try {
+            const res = await fetch(`/api/auth/users/${encodeURIComponent(oldUsername)}/rename`, {
+              method: 'PUT',
+              credentials: 'same-origin',
+              headers: { 'Content-Type': 'application/json' },
+              body: JSON.stringify({ username }),
+            });
+            const data = await res.json().catch(() => ({}));
+            if (!res.ok) {
+              uiModule.showError(data.detail || 'Failed to rename user');
+              return;
+            }
+            if (data.renamed_self) {
+              window.location.reload();
+              return;
+            }
+            loadUsers();
+          } catch (err) {
+            uiModule.showError('Failed to rename user');
+          }
+        });
+      }
+
       // Delete button
       const delBtn = row.querySelector('[data-adm-del-user]');
       if (delBtn) {