Refactor palette keyboard focus handling

Ensure proper focus management when switching between browse and
search modes, and avoid double-handling keyboard events when the
name input is active.

frontend/js/palette.js

@@ -132,6 +132,7 @@ function askName() {
     } else if (e.key === 'Escape') {
       e.preventDefault();
       cleanupNameInput();
+      _overlay.focus();
       renderBrowse();
     }
   });
@@ -140,7 +141,6 @@ function askName() {
 function cleanupNameInput() {
   const el = document.getElementById('cp-name-input');
   if (el) el.remove();
-  _input.style.display = '';
   const bc = document.getElementById('cp-breadcrumb');
   if (bc) bc.style.display = 'flex';
 }
@@ -196,6 +196,7 @@ function createDOM() {
   if (_overlay) return;
   _overlay = document.createElement('div');
   _overlay.className = 'command-palette-overlay';
+  _overlay.tabIndex = -1;  // needed to receive keyboard events when input is hidden (browse mode)
   _overlay.innerHTML = `<div class="command-palette">
     <div class="cp-header"><input type="text" class="cp-input" placeholder="Rechercher un fichier... (tapez > pour les commandes)" spellcheck="false" autocomplete="off"><div class="cp-breadcrumb" id="cp-breadcrumb"></div><span class="cp-hint">Ctrl+Shift+Espace</span></div>
     <div class="cp-results"></div>
@@ -237,8 +238,10 @@ function switchMode(m) {
   _mode = m;
   if (m === 'browse' || m === 'browse-vault') {
     _input.style.display = 'none'; _input.disabled = true;
+    _overlay.focus();  // overlay receives keyboard events when input is hidden
   } else {
     _input.style.display = ''; _input.disabled = false;
+    _input.focus();  // restore focus to search input
     const bc = document.getElementById('cp-breadcrumb'); if (bc) bc.style.display = 'none';
   }
 }
@@ -309,6 +312,8 @@ function scroll() { const s = _results.querySelector('.cp-selected'); if (s) s.s
 // ── Overlay keydown handler (for browse modes where input is hidden) ──
 function onOverlayKeyDown(e) {
   if (_mode !== 'browse' && _mode !== 'browse-vault') return;
+  // Don't handle if name input is active (it has its own keydown handler)
+  if (document.getElementById('cp-name-input')) return;
   onKeyDown(e);
 }