feat: integrate client and server sharing workflows

web/src/features/channel/Workspace.module.css

@@ -68,3 +68,15 @@
   font-size: 18px;
   pointer-events: none;
 }
+
+.error {
+  position: fixed;
+  top: var(--bar-h);
+  left: var(--space-4);
+  right: var(--space-4);
+  z-index: 20;
+  padding: var(--space-3);
+  background: var(--surface);
+  color: var(--danger);
+  border: 1px solid var(--danger);
+}

web/src/features/channel/Workspace.tsx

@@ -33,6 +33,7 @@ export function Workspace() {
   const sendFiles = useWorkspace((s) => s.sendFiles);
   const sendText = useWorkspace((s) => s.sendText);
   const remove = useWorkspace((s) => s.remove);
+  const error = useWorkspace((s) => s.error);
   const download = useDownload();
 
   // 刚创建的频道:直接展示分享面板和二维码,让对方马上能扫
@@ -61,10 +62,7 @@ export function Workspace() {
 
   // 从首页「快速分享」带过来的内容,进入频道后发送
   useEffect(() => {
-    const { consumePayload, clearJustCreated } = useChannels.getState();
-    const p = consumePayload();
-    if (p) sendPayload(p);
-    clearJustCreated();
+    useChannels.getState().clearJustCreated();
   }, [sendPayload]);
 
   const ids = useWorkspace(
@@ -192,6 +190,7 @@ export function Workspace() {
         </div>
       )}
 
+      {error ? <div className={styles.error} role="alert">{error}</div> : null}
       {!desktop && panelOpen ? (
         <Sheet title="设备与分享" onClose={closePanel}>
           <DevicePanel qrOpen={justCreated} />