Polish: UI theme colors, onboarding dismiss, Export button in sidebar (#270)

* Light mode style fixes

* Fix dismissing onboarding for nested routes

* Refactor: move export button to  user side panel

* Refactor: add project data to modeling page loader

* Add new ProjectSidebarMenu

* Convert AppHeader to use ProjectSidebarMenu

* Move ExportButton to ProjectSidebarMenu

* Fix: hide default dir setting in Web

* Add DownloadAppBanner when in Prod

* Add unit tests to ProjectSidebarMenu

* Tiny CSS rounding tweak to sidebars

* Fix formatting in unit tests

* Update icons and logos to use full-color Kitt

* Fix: dim UI on camera drag, not click

src/Toolbar.tsx

@@ -32,7 +32,6 @@ export const Toolbar = () => {
 
   return (
     <div>
-      <ExportButton />
       {guiMode.mode === 'default' && (
         <button
           onClick={() => {