Fix CSP-blocked command palette trigger (inline onclick -> addEventListener)

The ⌘K header button used an inline onclick handler, which the CSP
(script-src-attr, nonce-based, no unsafe-inline) blocks, so clicking the
button did nothing. Move the handler into the existing nonce'd script
block and bind it via addEventListener on #lt-cmd-trigger.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

views/layout_header.php

@@ -205,7 +205,6 @@ $_lt_assetVer  = $GLOBALS['config']['ASSET_VERSION'] ?? '20260329';
               class="lt-btn lt-btn-ghost lt-btn-sm"
               title="Command palette (Ctrl+K)"
               aria-label="Open command palette"
-              onclick="if(window.lt&&lt.cmdPalette)lt.cmdPalette.open()"
               style="font-size:0.65rem;opacity:0.65;letter-spacing:0.03em;padding:0.2rem 0.45rem">&#x2315;&nbsp;K</button>
       <button type="button" class="lt-theme-btn" id="lt-theme-btn"
               aria-label="Switch to light mode" title="Switch to light mode">&#x2600;</button>
@@ -258,6 +257,13 @@ $_lt_assetVer  = $GLOBALS['config']['ASSET_VERSION'] ?? '20260329';
         });
       } catch(_) {}
       if (window.lt && lt.cmdPalette) lt.cmdPalette.init(commands);
+      // Bind the header ⌘K trigger here (no inline onclick — CSP blocks inline handlers)
+      var cmdTrigger = document.getElementById('lt-cmd-trigger');
+      if (cmdTrigger) {
+        cmdTrigger.addEventListener('click', function() {
+          if (window.lt && lt.cmdPalette) lt.cmdPalette.open();
+        });
+      }
     });
     // Keyboard shortcut: Ctrl+K / Cmd+K
     document.addEventListener('keydown', function(e) {