feat: add onboarding for client (#2144)

Co-authored-by: Himself65 <himself65@outlook.com>

apps/web/src/components/blocksuite/workspace-header/header-right-items/EditorOptionMenu.tsx

@@ -45,7 +45,7 @@ const CommonMenu = () => {
       <Menu
         width={276}
         content={content}
-        // placement="bottom-end"
+        placement="bottom"
         disablePortal={true}
         trigger="click"
       >

apps/web/src/components/blocksuite/workspace-header/styles.ts

@@ -15,7 +15,7 @@ export const StyledHeaderContainer = styled('div')<{
     top: 0,
     background: 'var(--affine-background-primary-color)',
     WebkitAppRegion: 'drag',
-    zIndex: 1,
+    zIndex: 'var(--affine-z-index-popover)',
     '@media (max-width: 768px)': {
       '&[data-open="true"]': {
         WebkitAppRegion: 'no-drag',