Fix builder page layout: make new chat and history buttons sticky at top on desktop

- Moved sticky positioning from mobile-only to global CSS for .top-left-actions

- Buttons now stay fixed at top above content on all screen sizes

- Includes various other app updates (version management, server improvements)

chat/public/builder.html

@@ -81,6 +81,16 @@
       align-items: center;
       gap: 8px;
       margin-bottom: 12px;
+      position: sticky;
+      top: 0;
+      z-index: 1000;
+      background: rgba(247, 249, 251, 0.8);
+      backdrop-filter: blur(10px);
+      -webkit-backdrop-filter: blur(10px);
+      padding: 10px 16px;
+      width: 100%;
+      box-sizing: border-box;
+      border-bottom: 1px solid rgba(0, 0, 0, 0.05);
     }
 
     .header-left {
@@ -876,17 +886,7 @@
 
     @media (max-width: 640px) {
       .top-left-actions {
-        position: sticky;
-        top: 0;
-        z-index: 1000;
-        background: rgba(247, 249, 251, 0.8);
-        backdrop-filter: blur(10px);
-        -webkit-backdrop-filter: blur(10px);
-        padding: 10px 16px;
         margin-bottom: 0;
-        width: 100%;
-        box-sizing: border-box;
-        border-bottom: 1px solid rgba(0, 0, 0, 0.05);
       }
 
       .app-shell.builder-single {