完善机构终端页面布局与登录页细节调整

frontend/components/dashboard/ScanTerminalDashboard.tsx

@@ -282,6 +282,13 @@ function KoyfinWeatherTerminal({
   return (
     <div className="flex h-screen w-full overflow-hidden bg-[#e9edf3] text-[#202833]">
       <aside className="flex w-[52px] shrink-0 flex-col items-center gap-2 bg-[#171d24] py-4 text-slate-300">
+        <Link
+          href="/"
+          className="mb-2 grid h-8 w-8 place-items-center rounded bg-blue-600 text-white transition hover:bg-blue-700"
+          title="PolyWeather"
+        >
+          <CloudSun size={18} />
+        </Link>
         <Menu size={23} className="mb-3" />
         {[CloudSun, Table2, BarChart3, LineChart, Gauge, Bell].map((Icon, i) => (
           <button
@@ -564,10 +571,12 @@ function ProductAccessRequired({
       <aside className="w-[52px] bg-[#171d24]" />
       <main className="flex flex-1 flex-col">
         <header className="flex h-[64px] items-center justify-between bg-[#171d24] px-4 text-white">
-          <div className="flex items-center gap-3 font-black">
-            <CloudSun size={21} />
-            PolyWeather Terminal
-          </div>
+          <Link href="/" className="flex items-center gap-3 font-black hover:opacity-90">
+            <span className="grid h-8 w-8 place-items-center rounded bg-blue-600 text-white">
+              <CloudSun size={18} />
+            </span>
+            <span>PolyWeather Terminal</span>
+          </Link>
           <div className="font-mono text-sm text-slate-300">{userLocalTime}</div>
         </header>
         <section className="grid flex-1 place-items-center p-6">