feat: 重设计私信页并优化开源展柜体验

私信改为飞书风布局，支持缩略图表情/图片、按会话草稿与用户搜索发起会话；主页发私信直达消息页。开源展柜修复空列表粘滞并改版目录式 UI。

frontend/src/components/PostAuthorCard.tsx

@@ -9,7 +9,6 @@ import { useAuth } from '../hooks/useAuth';
 import { loginPath } from '../utils/authRedirect';
 import { formatTime } from '../utils/content';
 import { userPath } from '../utils/userPath';
-import ComposeMessageDialog from './ComposeMessageDialog';
 import UserLink from './UserLink';
 
 interface Props {
@@ -28,7 +27,6 @@ export default function PostAuthorCard({
   const { user: me } = useAuth();
   const [profile, setProfile] = useState<UserPublic | null>(null);
   const [stats, setStats] = useState<UserActivityStats | null>(null);
-  const [msgOpen, setMsgOpen] = useState(false);
 
   useEffect(() => {
     if (!author?.id) {
@@ -78,7 +76,7 @@ export default function PostAuthorCard({
       nav(loginPath(profileHref));
       return;
     }
-    setMsgOpen(true);
+    nav(`/messages?peer=${author.id}`);
   };
 
   return (
@@ -159,16 +157,6 @@ export default function PostAuthorCard({
           </Button>
         </div>
       </div>
-
-      {!isSelf && (
-        <ComposeMessageDialog
-          open={msgOpen}
-          onOpenChange={setMsgOpen}
-          toUserId={author.id}
-          toNickname={nick}
-          onSent={() => nav(`/messages?peer=${author.id}`)}
-        />
-      )}
     </div>
   );
 }

frontend/src/components/PullToRefresh.tsx

@@ -31,7 +31,7 @@ function pickScrollEl(): HTMLElement | null {
   const page = document.querySelector<HTMLElement>('.page-wrap:not(.page-wrap--feed)');
   if (page) return page;
 
-  const showcase = document.querySelector<HTMLElement>('.showcase-page');
+  const showcase = document.querySelector<HTMLElement>('.showcase-panel');
   if (showcase) return showcase.closest<HTMLElement>('.main-content') ?? showcase;
 
   const admin = document.querySelector<HTMLElement>('.admin-main');

frontend/src/components/ShowcaseAsideWidget.tsx

@@ -19,12 +19,14 @@ export default function ShowcaseAsideWidget() {
   useEffect(() => {
     let cancelled = false;
     const hit = getSessionSnapshot<CommunityShowcaseItem[]>(SHOWCASE_KEY);
-    if (hit !== undefined) {
+    // 非空快照直接用；空数组可能是启动竞态假空，仍再拉
+    if (hit !== undefined && hit.length > 0) {
       setItems(hit);
       setLoading(false);
       return;
     }
-    setLoading(true);
+    if (hit !== undefined) setItems(hit);
+    setLoading(hit === undefined);
     api.communityShowcase()
       .then((r) => {
         if (cancelled) return;
@@ -33,10 +35,8 @@ export default function ShowcaseAsideWidget() {
         setItems(next);
       })
       .catch(() => {
-        if (!cancelled) {
-          setSessionSnapshot(SHOWCASE_KEY, []);
-          setItems([]);
-        }
+        // 失败不写空快照，避免假空粘死
+        if (!cancelled && hit === undefined) setItems([]);
       })
       .finally(() => {
         if (!cancelled) setLoading(false);
@@ -54,17 +54,13 @@ export default function ShowcaseAsideWidget() {
           setItems(next);
         })
         .catch(() => {
-          if (opts.showLoading) {
-            setSessionSnapshot(SHOWCASE_KEY, []);
-            setItems([]);
-          }
-          // 软刷新失败：保持旧 UI
+          // 软刷新 / 强刷失败：保持旧 UI，不写空快照
         })
         .finally(() => setLoading(false));
     };
     const applyHitOrReload = (showLoading: boolean) => {
       const hit = getSessionSnapshot<CommunityShowcaseItem[]>(SHOWCASE_KEY);
-      if (hit !== undefined) {
+      if (hit !== undefined && hit.length > 0) {
         setItems(hit);
         setLoading(false);
         return;