fix(navbar): restore small caret icon on right-menu dropdowns

The "+", theme switcher, and Settings dropdowns in the navbar's right
menu were switched from Icons.CaretDownOutlined to Icons.DownOutlined,
whose glyph fills noticeably more of its bounding box even at the same
iconSize="xs", making the caret look larger and inconsistent with the
language picker's caret (still CaretDownOutlined) in the same menu.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: juliannfpreset

superset-frontend/src/features/home/RightMenu.tsx

@@ -614,7 +614,7 @@ const RightMenu = ({
         key: 'new-dropdown',
         label: <Icons.PlusOutlined data-test="new-dropdown-icon" />,
         className: 'submenu-with-caret',
-        icon: <Icons.DownOutlined iconSize="xs" />,
+        icon: <Icons.CaretDownOutlined iconSize="xs" />,
         children: buildNewDropdownItems(),
         popupOffset: NAVBAR_MENU_POPUP_OFFSET,
       });
@@ -631,7 +631,7 @@ const RightMenu = ({
     items.push({
       key: 'settings',
       label: t('Settings'),
-      icon: <Icons.DownOutlined iconSize="xs" />,
+      icon: <Icons.CaretDownOutlined iconSize="xs" />,
       children: buildSettingsMenuItems(),
       className: 'submenu-with-caret',
       popupOffset: NAVBAR_MENU_POPUP_OFFSET,

superset-frontend/src/hooks/useThemeMenuItems.tsx

@@ -136,7 +136,7 @@ export const useThemeMenuItems = ({
   return {
     key: 'theme-sub-menu',
     label: selectedThemeModeIcon,
-    icon: <Icons.DownOutlined iconSize="xs" />,
+    icon: <Icons.CaretDownOutlined iconSize="xs" />,
     className: 'submenu-with-caret',
     children,
     popupOffset: NAVBAR_MENU_POPUP_OFFSET,