notes(ui): polling 静默 refresh + 增量更新 list/selected，不再闪动

apps/notes/frontend/src/App.vue

@@ -235,16 +235,39 @@ function logout() {
   stopPoll()
 }
 
-async function refresh() {
-  loading.value = true
-  try { list.value = await listRecordings() }
+async function refresh(silent = false) {
+  if (!silent) loading.value = true
+  try {
+    const fresh = await listRecordings()
+    // 增量更新：尽量复用已有 ref，避免整 array 替换导致闪动
+    if (!list.value.length) {
+      list.value = fresh
+    } else {
+      const byId = new Map(list.value.map(r => [r.id, r]))
+      list.value = fresh.map(r => {
+        const old = byId.get(r.id)
+        if (old) {
+          Object.assign(old, r)
+          return old
+        }
+        return r
+      })
+    }
+  }
   catch (e) {
     if (e.unauthorized) { logout(); return }
   }
-  finally { loading.value = false }
+  finally { if (!silent) loading.value = false }
   // 同步当前选中
   if (selectedId.value) {
-    try { selected.value = await getRecording(selectedId.value) } catch {}
+    try {
+      const fresh = await getRecording(selectedId.value)
+      if (selected.value) {
+        Object.assign(selected.value, fresh)
+      } else {
+        selected.value = fresh
+      }
+    } catch {}
   }
 }
 
@@ -336,7 +359,7 @@ function mdLite(s) {
 
 function startPoll() {
   stopPoll()
-  pollTimer = setInterval(refresh, 5000)
+  pollTimer = setInterval(() => refresh(true), 5000)
 }
 function stopPoll() {
   if (pollTimer) { clearInterval(pollTimer); pollTimer = null }