Fix first worktree card top border cutoff (#15)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

src/renderer/src/components/sidebar/WorktreeList.tsx

@@ -357,7 +357,7 @@ const WorktreeList = React.memo(function WorktreeList() {
   }
 
   return (
-    <div ref={scrollRef} className="flex-1 overflow-auto px-1 scrollbar-sleek scroll-smooth">
+    <div ref={scrollRef} className="flex-1 overflow-auto px-1 pt-px scrollbar-sleek scroll-smooth">
       <div className="relative w-full" style={{ height: `${virtualizer.getTotalSize()}px` }}>
         {virtualizer.getVirtualItems().map((vItem) => {
           const row = rows[vItem.index]