fix: 手机左右滑动切换 tab 不生效

- 加 touch-action: pan-y 阻止浏览器抢占水平手势
- 用 touchmove 实时跟踪手指位置（比 touchend.changedTouches 更可靠）
- 用 touchstart 的 target 判断 no-swipe 区域（手指移动后 target 可能变）
- 弹窗/遮罩层打开时跳过滑动切换
- 阈值从 50px 调到 60px 减少误触

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/App.vue

@@ -38,7 +38,7 @@
   </div>
 
   <!-- Main content -->
-  <div class="main" @touchstart="onSwipeStart" @touchend="onSwipeEnd">
+  <div class="main" @touchstart.passive="onSwipeStart" @touchmove.passive="onSwipeMove" @touchend="onSwipeEnd" style="touch-action: pan-y">
     <router-view />
   </div>
 
@@ -167,23 +167,36 @@ function toggleUserMenu() {
 }
 
 // ── 左右滑动切换 tab ──
-// 滑动顺序 = visibleTabs 的顺序（根据用户角色动态决定）
-// 轮播区域（data-no-tab-swipe）内的滑动不触发 tab 切换
+// touch-action: pan-y on .main tells the browser to only handle vertical scroll natively,
+// leaving horizontal swipe gestures to our JS handler.
 const swipeStartX = ref(0)
 const swipeStartY = ref(0)
+const swipeEndX = ref(0)
+const swipeEndY = ref(0)
+const swipeStartTarget = ref(null)
 
 function onSwipeStart(e) {
   swipeStartX.value = e.touches[0].clientX
   swipeStartY.value = e.touches[0].clientY
+  swipeEndX.value = e.touches[0].clientX
+  swipeEndY.value = e.touches[0].clientY
+  swipeStartTarget.value = e.target
 }
 
-function onSwipeEnd(e) {
-  const dx = e.changedTouches[0].clientX - swipeStartX.value
-  const dy = e.changedTouches[0].clientY - swipeStartY.value
-  // 必须是水平滑动 > 50px，且水平距离大于垂直距离
-  if (Math.abs(dx) < 50 || Math.abs(dy) > Math.abs(dx)) return
-  // 轮播区域内不触发 tab 切换
-  if (e.target.closest && e.target.closest('[data-no-tab-swipe]')) return
+function onSwipeMove(e) {
+  swipeEndX.value = e.touches[0].clientX
+  swipeEndY.value = e.touches[0].clientY
+}
+
+function onSwipeEnd() {
+  const dx = swipeEndX.value - swipeStartX.value
+  const dy = swipeEndY.value - swipeStartY.value
+  // Must be primarily horizontal (>60px) and more horizontal than vertical
+  if (Math.abs(dx) < 60 || Math.abs(dy) > Math.abs(dx)) return
+  // Carousel area excluded
+  if (swipeStartTarget.value?.closest?.('[data-no-tab-swipe]')) return
+  // Skip when modal/overlay is open
+  if (document.querySelector('.modal-overlay, .detail-overlay, .dialog-overlay')) return
 
   const tabs = visibleTabs.value.map(t => t.key)
   const currentIdx = tabs.indexOf(ui.currentSection)
@@ -193,8 +206,7 @@ function onSwipeEnd(e) {
   if (dx < 0 && currentIdx < tabs.length - 1) nextIdx = currentIdx + 1
   else if (dx > 0 && currentIdx > 0) nextIdx = currentIdx - 1
   if (nextIdx >= 0) {
-    const tab = visibleTabs.value[nextIdx]
-    handleTabClick(tab)
+    handleTabClick(visibleTabs.value[nextIdx])
   }
 }