fix(frontend): commit Select choice on pointerdown to avoid portal race

When the dropdown is rendered through createPortal under document.body,
the document-level outside-click listener and the option's React onClick
can race in certain DOM/Radix contexts: the outside-click handler fires
on mousedown bubble, which can unmount the portal before the option's
click ever reaches React, leaving the user unable to pick a value.

Switch the listener to pointerdown (rejecting only targets outside both
the trigger and the portaled dropdown) and commit selection from the
option's onPointerDown handler with preventDefault. The onClick handler
stays as a keyboard-triggered fallback for Enter/Space.

Author: james-6-23

frontend/src/components/ui/select.tsx

@@ -71,8 +71,13 @@ export function Select({
   useEffect(() => {
     if (!open) return
 
-    const handlePointerDown = (event: MouseEvent) => {
-      const target = event.target as Node
+    // 关闭仅在「点击 trigger 与 dropdown 之外」触发。注意 dropdown 通过 createPortal
+    // 渲染在 document.body 下，与 trigger 不在同一 DOM 子树，必须按 ref 直接判断。
+    // 用 pointerdown 而非 mousedown，能同时覆盖鼠标 / 触屏 / 笔，且对路径上的 React
+    // 合成事件 stopPropagation 不敏感（native 监听拿到的总是真实 target）。
+    const handlePointerDown = (event: PointerEvent) => {
+      const target = event.target as Node | null
+      if (!target) return
       if (triggerRef.current?.contains(target)) return
       if (dropdownRef.current?.contains(target)) return
       setOpen(false)
@@ -86,19 +91,27 @@ export function Select({
 
     const handleReposition = () => computePosition()
 
-    document.addEventListener('mousedown', handlePointerDown)
+    document.addEventListener('pointerdown', handlePointerDown)
     document.addEventListener('keydown', handleEscape)
     window.addEventListener('resize', handleReposition)
     window.addEventListener('scroll', handleReposition, true)
 
     return () => {
-      document.removeEventListener('mousedown', handlePointerDown)
+      document.removeEventListener('pointerdown', handlePointerDown)
       document.removeEventListener('keydown', handleEscape)
       window.removeEventListener('resize', handleReposition)
       window.removeEventListener('scroll', handleReposition, true)
     }
   }, [open, computePosition])
 
+  const handleSelect = useCallback(
+    (next: string) => {
+      onValueChange(next)
+      setOpen(false)
+    },
+    [onValueChange]
+  )
+
   return (
     <div className={cn('relative w-full', className)}>
       <button
@@ -163,10 +176,17 @@ export function Select({
                             ? 'bg-primary/10 text-primary'
                             : 'text-foreground hover:bg-accent/70 hover:text-accent-foreground'
                         )}
-                        onClick={() => {
-                          onValueChange(option.value)
-                          setOpen(false)
+                        // 用 onPointerDown 在 target 阶段直接 commit 选择：
+                        //  1. 早于 document 的 outside-pointerdown handler，避免 portal 边界
+                        //     场景下 dropdown 被先关掉、click 永远收不到的竞态；
+                        //  2. preventDefault 阻止 button 的默认 focus 转移，下拉关闭时焦点自然
+                        //     回到 trigger，不会跳到无关元素。
+                        onPointerDown={(event) => {
+                          event.preventDefault()
+                          handleSelect(option.value)
                         }}
+                        // onClick 兜底：键盘 Enter / Space 触发的合成 click 没有 pointerdown。
+                        onClick={() => handleSelect(option.value)}
                       >
                         <span className="truncate">{option.label}</span>
                         <Check className={cn('size-4 shrink-0', isSelected ? 'opacity-100' : 'opacity-0')} />