feat: enhance download manager with folder notes and improved worker settings

ui/src/App.vue

@@ -170,7 +170,7 @@ const settings = ref({
   adbMode: "device" as "device" | "settings",
   custom: { ...builtinDevice.value },
   proxy: emptyProxy(),
-  workers: 2,
+  workers: 6,
   directory: "",
   defaultDirectory: "",
 });
@@ -241,7 +241,7 @@ async function loadDeviceDefaults() {
 
 function normalizeWorkers(value: unknown) {
   const count = Number(value);
-  if (!Number.isInteger(count) || count < 1 || count > 8) return 2;
+  if (!Number.isInteger(count) || count < 1) return 6;
   return count;
 }
 
@@ -302,7 +302,7 @@ async function saveSettings() {
   const workers = normalizeWorkers(draft.value.workers);
   if (workers !== Number(draft.value.workers)) {
     settingsTab.value = "download";
-    settingsError.value = "同时下载数量需要在 1 到 8 之间";
+    settingsError.value = "同时下载数量至少为 1";
     return;
   }
   const directory = draft.value.directory.trim();
@@ -365,7 +365,7 @@ function restoreCurrent() {
     draft.value.proxy = emptyProxy();
     return;
   }
-  draft.value.workers = 2;
+  draft.value.workers = 6;
   draft.value.directory = draft.value.defaultDirectory || settings.value.defaultDirectory;
 }
 

ui/src/views/SettingsPanel.vue

@@ -150,11 +150,11 @@ function setDraftField(key: keyof DeviceProfile, value: string | boolean) {
                 <template #trigger>
                   <span class="help-dot" tabindex="0">?</span>
                 </template>
-                同时进行的下载任务数，范围 1 到 8，默认 2。调低后，多出来的任务会在当前这部下完后停下来。
+                同时进行的下载任务数，至少 1 个，默认 6。调低后，多出来的任务会在当前这部下完后停下来。
               </n-tooltip>
             </span>
           </template>
-          <n-input-number v-model:value="draft.workers" class="worker-input" button-placement="both" :min="1" :max="8" :precision="0" />
+          <n-input-number v-model:value="draft.workers" class="worker-input" button-placement="both" :min="1" :precision="0" />
         </n-form-item>
       </n-form>
     </n-tab-pane>

ui/src/views/VideoListPage.vue

@@ -84,6 +84,10 @@ function toggleSection(section: Section, checked: boolean) {
   selected.value = next;
 }
 
+function clearSelection() {
+  selected.value = new Set();
+}
+
 function pruneSelection() {
   const ids = new Set(sections.value.flatMap((section) => section.items.map((item) => item.id)));
   selected.value = new Set([...selected.value].filter((id) => ids.has(id)));
@@ -417,7 +421,10 @@ async function startDownload() {
       </div>
     </div>
     <footer class="download-foot">
-      <n-text>已选 {{ selected.size }} 部</n-text>
+      <div class="foot-selected">
+        <n-text>已选 {{ selected.size }} 部</n-text>
+        <n-button secondary size="small" :disabled="selected.size === 0" @click="clearSelection">取消选择</n-button>
+      </div>
       <div class="foot-actions">
         <n-text class="foot-dir" depth="3" :title="directory">{{ directory || "未设置下载目录" }}</n-text>
         <n-button secondary size="small" @click="chooseDirectory">选择</n-button>
@@ -445,6 +452,7 @@ async function startDownload() {
   background: #18181c;
 }
 .foot-actions { display: flex; align-items: center; gap: 8px; min-width: 0; }
+.foot-selected { display: flex; align-items: center; gap: 8px; flex: none; }
 .foot-dir { max-width: 420px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
 .foot-error { display: block; padding: 0 20px 8px; text-align: right; }
 .catalog-error { margin: 8px 20px 12px; }