refactor(dashboard): reorganize menu actions across sidebar/header/profile

Move shutdown into header popup + profile, move remote into sidebar above
settings, add flag-only language switcher in header, and add language card
plus shutdown/logout actions to the profile page.

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

src/shared/components/HeaderLanguage.js

@@ -0,0 +1,46 @@
+"use client";
+
+import { useState, useEffect } from "react";
+import { LOCALE_COOKIE, normalizeLocale } from "@/i18n/config";
+import { LOCALE_FLAGS } from "@/shared/constants/locales";
+import LanguageSwitcher from "./LanguageSwitcher";
+
+function getLocaleFromCookie() {
+  if (typeof document === "undefined") return "en";
+  const cookie = document.cookie
+    .split(";")
+    .find((c) => c.trim().startsWith(`${LOCALE_COOKIE}=`));
+  const value = cookie ? decodeURIComponent(cookie.split("=")[1]) : "en";
+  return normalizeLocale(value);
+}
+
+export default function HeaderLanguage() {
+  const [open, setOpen] = useState(false);
+  const [locale, setLocale] = useState("en");
+
+  useEffect(() => {
+    setLocale(getLocaleFromCookie());
+  }, [open]);
+
+  return (
+    <>
+      <button
+        onClick={() => setOpen(true)}
+        className="flex items-center justify-center p-2 rounded-lg text-text-muted hover:text-text-main hover:bg-black/5 dark:hover:bg-white/5 transition-all"
+        title="Language"
+        data-i18n-skip="true"
+      >
+        <span className="text-lg leading-none">{LOCALE_FLAGS[locale] || "🌐"}</span>
+      </button>
+
+      <LanguageSwitcher
+        hideTrigger
+        isOpen={open}
+        onClose={(next) => {
+          setOpen(false);
+          setLocale(next);
+        }}
+      />
+    </>
+  );
+}