chore(ui): tighten dropdown sub-trigger spacing (#47355)

## What kind of change does this PR introduce?

UI polish.  

## What is the current behavior?

Dropdown sub-menu triggers use symmetric padding and a heavier chevron.

## What is the new behavior?

Tighter right padding and a smaller, muted chevron.

| Before | After |
| --- | --- |
| <img width="1170" height="672" alt="CleanShot 2026-06-26 at 17 07
18@2x-4BDA3F92-78B4-45F4-B31E-897FF1FE537E"
src="https://github.com/user-attachments/assets/ade505c7-f4b0-4046-a728-c49ee93009d4"
/> | <img width="1168" height="672" alt="CleanShot 2026-06-26 at 17 06
33@2x-9A8992B6-C389-4698-BE19-7AEE3FB12A83"
src="https://github.com/user-attachments/assets/c1c9ba73-e059-45a1-82f3-5c268f060e2f"
/> |

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Bug Fixes**
* Improved dropdown submenu trigger spacing and alignment for a cleaner,
more consistent menu layout.
* Updated the trailing chevron icon’s positioning and sizing to keep it
consistently aligned at the far right across states.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Cursor <cursoragent@cursor.com>

packages/ui/src/components/shadcn/ui/dropdown-menu.tsx

@@ -32,14 +32,14 @@ const DropdownMenuSubTrigger = React.forwardRef<
   <DropdownMenuPrimitive.SubTrigger
     ref={ref}
     className={cn(
-      'flex cursor-default select-none items-center rounded-xs px-2 py-1.5 text-xs outline-hidden focus:bg-overlay-hover data-[state=open]:bg-overlay-hover',
+      'flex cursor-default select-none items-center rounded-xs pl-2 pr-1 py-1.5 text-xs outline-hidden focus:bg-overlay-hover data-[state=open]:bg-overlay-hover',
       inset && 'pl-8',
       className
     )}
     {...props}
   >
     {children}
-    <ChevronRight className="h-4 w-4 ml-auto!" />
+    <ChevronRight className="ml-auto! shrink-0 text-foreground-lighter" size={12} />
   </DropdownMenuPrimitive.SubTrigger>
 ))
 DropdownMenuSubTrigger.displayName = DropdownMenuPrimitive.SubTrigger.displayName