fix(initial-load): prevent FOUC on initial load

Author: danivek

src/index.html

@@ -53,6 +53,17 @@ <h1>JSONLab</h1>
                     <i data-lucide="moon" id="theme-icon"></i>
                 </button>
             </div>
+            <script>
+                // prevent FOUC: activate the correct mode button before first paint
+                (function () {
+                    var mode = localStorage.getItem('jsonlab_global_view_mode') || 'normal';
+                    if (mode !== 'normal') {
+                        document.getElementById('btn-mode-normal').classList.remove('active');
+                        var btn = document.getElementById('btn-mode-' + mode);
+                        if (btn) btn.classList.add('active');
+                    }
+                })();
+            </script>
         </header>
 
         <!-- Main Editor Area -->

src/js/app.js

@@ -51,7 +51,7 @@ const App = {
     rightContainer.className = 'editor-wrapper';
     rightContainer.id = 'editor-wrapper-right';
     rightContainer.style.flex = '1';
-    rightContainer.style.display = 'flex';
+    rightContainer.style.display = 'none'; // hidden until switchGlobalMode sets the correct layout
     rightContainer.style.flexDirection = 'column';
     rightContainer.style.minWidth = '0';
     container.appendChild(rightContainer);