Open editor by default

Remove 'collapsed' class so editor sidebar is visible on page load.

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Co-Authored-By: Claude <[email protected]>

Author: stared

index.html

@@ -37,7 +37,7 @@ <h1 id="equation-title">Interactive Equations</h1>
         </footer>
       </main>
 
-      <aside id="editor-sidebar" class="editor-sidebar collapsed">
+      <aside id="editor-sidebar" class="editor-sidebar">
         <div class="editor-toolbar">
           <button id="toggle-editor-btn" class="toolbar-btn" title="Show/hide editor">
             <span class="icon">◀</span>