Add Beijing time clock to control header top-right.

Co-authored-by: Cursor <cursoragent@cursor.com>

control/frontend/src/App.tsx

@@ -12,6 +12,33 @@ import MonitorPage from "./pages/Monitor";
 import SettingsPage from "./pages/Settings";
 import StatsPage from "./pages/Stats";
 
+function formatBeijingTime(ms: number): string {
+  return new Date(ms).toLocaleString("zh-CN", {
+    timeZone: "Asia/Shanghai",
+    hour12: false,
+    year: "numeric",
+    month: "2-digit",
+    day: "2-digit",
+    hour: "2-digit",
+    minute: "2-digit",
+    second: "2-digit",
+  });
+}
+
+function BeijingClock() {
+  const [nowMs, setNowMs] = useState(() => Date.now());
+  useEffect(() => {
+    const t = window.setInterval(() => setNowMs(Date.now()), 1000);
+    return () => window.clearInterval(t);
+  }, []);
+  return (
+    <div className="header-beijing-time" title="Asia/Shanghai">
+      <span className="header-beijing-label">北京时间</span>
+      <span className="mono header-beijing-value">{formatBeijingTime(nowMs)}</span>
+    </div>
+  );
+}
+
 function Shell({ children }: { children: ReactNode }) {
   const user = getUsername();
   const [lanClient, setLanClient] = useState(false);
@@ -30,6 +57,7 @@ function Shell({ children }: { children: ReactNode }) {
             <div className="header-title">对冲舰队指挥中心</div>
             <div className="header-subtitle">—— 比特骆驼定制开发</div>
           </div>
+          <BeijingClock />
         </div>
         <div className="header-bar">
           <nav className="nav">

control/frontend/src/styles.css

@@ -58,10 +58,12 @@ body {
 }
 
 .header-top {
+  position: relative;
   display: flex;
   justify-content: center;
   align-items: flex-start;
   padding: 4px 0 2px;
+  min-height: 3.2rem;
 }
 
 .header-title-wrap {
@@ -99,6 +101,48 @@ body {
   text-decoration-color: rgba(0, 200, 255, 0.45);
 }
 
+.header-beijing-time {
+  position: absolute;
+  right: 0;
+  top: 50%;
+  transform: translateY(-50%);
+  display: flex;
+  flex-direction: column;
+  align-items: flex-end;
+  gap: 2px;
+  z-index: 1;
+  pointer-events: none;
+}
+
+.header-beijing-label {
+  font-size: 0.72rem;
+  letter-spacing: 0.12em;
+  color: var(--muted);
+}
+
+.header-beijing-value {
+  font-size: 0.95rem;
+  color: var(--accent);
+  text-shadow: var(--glow);
+  white-space: nowrap;
+}
+
+@media (max-width: 1100px) {
+  .header-top {
+    flex-direction: column;
+    align-items: center;
+    gap: 10px;
+    min-height: 0;
+  }
+
+  .header-beijing-time {
+    position: static;
+    transform: none;
+    align-items: center;
+    pointer-events: auto;
+  }
+}
+
 .header-bar {
   display: flex;
   align-items: center;