fix: dates follow the UI language, not the browser's

Seven sites formatted with a bare toLocaleString()/toLocaleDateString(), so an
English UI on a Hungarian machine printed Hungarian-shaped dates (and the reverse).
They now go through formatDateTime/formatDate, which take the i18n language.

frontend/src/components/About.tsx

@@ -4,13 +4,14 @@ import { useTranslation } from "react-i18next";
 import { Info, Sparkles } from "lucide-react";
 import { api } from "../lib/api";
 import { FRONTEND_VERSION, FRONTEND_SHA, FRONTEND_BUILD_DATE } from "../lib/version";
+import { formatDateTime } from "../lib/format";
 import { Button } from "./ui/Button";
 import Modal from "./ui/Modal";
 
 function fmtDate(d?: string | null): string {
   if (!d) return "—";
   const t = new Date(d);
-  return isNaN(t.getTime()) ? d : t.toLocaleString();
+  return isNaN(t.getTime()) ? d : formatDateTime(d);
 }
 
 // About dialog: app + build + schema versions (frontend/backend/database), plus a

frontend/src/components/AdminUsers.tsx

@@ -431,7 +431,7 @@ function PendingAccessRowView({
           {row.created_at && (
             <span>
               {t("users.pendingAccess.signedUp", {
-                time: new Date(row.created_at).toLocaleString(),
+                time: formatDateTime(row.created_at),
               })}
             </span>
           )}
@@ -619,7 +619,10 @@ function AdminInvites() {
               inv.invited_at
                 ? "settings.invites.inviteConfirmAgain"
                 : "settings.invites.inviteConfirm",
-              { email: inv.email, time: new Date(inv.invited_at ?? 0).toLocaleString() },
+              {
+                email: inv.email,
+                time: formatDateTime(inv.invited_at ?? new Date(0).toISOString()),
+              },
             )}
           </p>
           <InviteLangPicker initial={lang} onPick={(v) => (lang = v)} />
@@ -718,7 +721,7 @@ function AdminInvites() {
                     hint={
                       i.invited_at
                         ? t("settings.invites.invitedAt", {
-                            time: new Date(i.invited_at).toLocaleString(),
+                            time: formatDateTime(i.invited_at),
                           })
                         : t("settings.invites.inviteHint")
                     }
@@ -916,7 +919,7 @@ function InviteRow({
         {inv.requested_at && (
           <div className="text-2xs text-muted">
             {t("settings.invites.requested", {
-              time: new Date(inv.requested_at).toLocaleString(),
+              time: formatDateTime(inv.requested_at),
             })}
           </div>
         )}

frontend/src/components/ShareDialog.tsx

@@ -9,6 +9,7 @@ import { useConfirm } from "./ConfirmProvider";
 import { notify } from "../lib/notifications";
 import { notifyActionError } from "../lib/actionErrors";
 import { copyText } from "../lib/clipboard";
+import { formatDate } from "../lib/format";
 import { api, type DownloadJob, type ShareLink } from "../lib/api";
 import { inputCls } from "./ui/form";
 import { Button } from "./ui/Button";
@@ -88,7 +89,7 @@ function UserShare({ job }: { job: DownloadJob }) {
 // --- share by public link -------------------------------------------------------------------
 
 function LinkRow({ link, onChanged }: { link: ShareLink; onChanged: () => void }) {
-  const { t } = useTranslation();
+  const { t, i18n } = useTranslation();
   const confirm = useConfirm();
   const [copied, setCopied] = useState(false);
   const [editPass, setEditPass] = useState(false);
@@ -130,7 +131,7 @@ function LinkRow({ link, onChanged }: { link: ShareLink; onChanged: () => void }
   if (link.allow_download) badges.push(t("downloads.share.downloadable"));
   if (link.expires_at)
     badges.push(
-      t("downloads.share.expiresOn", { date: new Date(link.expires_at).toLocaleDateString() }),
+      t("downloads.share.expiresOn", { date: formatDate(link.expires_at, i18n.language) }),
     );
 
   return (

frontend/src/components/downloadRow.tsx

@@ -7,7 +7,14 @@ import { useLiveQuery } from "../lib/useLiveQuery";
 import { api, type DownloadJob } from "../lib/api";
 import { notify } from "../lib/notifications";
 import { copyText } from "../lib/clipboard";
-import { formatBytes, formatDuration, formatEta, formatSpeed, relativeTime } from "../lib/format";
+import {
+  formatBytes,
+  formatDateTime,
+  formatDuration,
+  formatEta,
+  formatSpeed,
+  relativeTime,
+} from "../lib/format";
 import { navItemAttrs } from "../lib/listNav";
 import { failCopyKeys } from "../lib/downloadFailure";
 
@@ -250,7 +257,7 @@ export function DownloadRow({
           {job.status === "done" && job.created_at ? (
             <span
               className="text-muted inline-flex items-center gap-1"
-              title={new Date(job.created_at).toLocaleString()}
+              title={formatDateTime(job.created_at)}
             >
               · <CalendarClock className="w-3.5 h-3.5" /> {relativeTime(job.created_at)}
             </span>