music(player): sidebar 双击切歌并播放（单击只切换不打扰）

apps/music/frontend/src/views/PlayerView.vue

@@ -68,6 +68,8 @@
             class="row"
             :class="{ active: selectedId === p.id }"
             @click="selectPiece(p.id)"
+            @dblclick="playPiece(p.id)"
+            title="单击切换 / 双击切换并播放"
           >
             <div class="row-main">
               <div class="row-title">{{ p.title }}</div>
@@ -773,9 +775,12 @@ async function loadPiece(id) {
     await nextTick()
     const first = audioAttachments.value[0]
     if (first && audioEl.value) {
-      // 优先用 IDB 缓存的 blob URL（cache 关时同步返回网络 URL，零延迟）
       audioEl.value.src = getAudioUrl(first.id)
-      if (wasPlaying) audioEl.value.play().catch(() => {})
+      // 续播条件：之前正在播 / 双击强制要求 / forceNextPlay flag
+      if (wasPlaying || forceNextPlay) {
+        audioEl.value.play().catch(() => {})
+      }
+      forceNextPlay = false
     } else if (audioEl.value) {
       audioEl.value.removeAttribute('src')
       audioEl.value.load()
@@ -804,6 +809,18 @@ function selectPiece(id) {
   router.push({ name: 'piece', params: { id } })
 }
 
+let forceNextPlay = false
+function playPiece(id) {
+  forceNextPlay = true
+  // 同 piece dblclick：URL 不变 watch 不触发 → 直接 play
+  if (id === selectedId.value && audioEl.value) {
+    audioEl.value.play().catch(() => {})
+    forceNextPlay = false
+    return
+  }
+  selectPiece(id)
+}
+
 function attachmentUrl(id) { return attUrl(id) }
 
 function togglePlay() {