refactor(i18n,format): translate ETA strings; consolidate time/duration formatters

- formatEta was hardcoded English (violated the trilingual rule) -> time.eta.* keys
  in EN/HU/DE; Scheduler's countdown 'now' likewise.
- relativeFromMs added to format.ts; NotificationsPanel drops its duplicate
  relativeTime/relativeFromMs and the now-orphaned notifications.time.* keys.
- Channels' fmtTotalDuration moved to format.ts as formatTotalHours.

frontend/src/components/Channels.tsx

@@ -15,7 +15,7 @@ import {
 } from "lucide-react";
 import { api, HttpError, type ManagedChannel, type Tag } from "../lib/api";
 import { useDismiss } from "../lib/useDismiss";
-import { formatEta, formatViews, relativeTime } from "../lib/format";
+import { formatEta, formatTotalHours, formatViews, relativeTime } from "../lib/format";
 import { notify } from "../lib/notifications";
 import Tooltip from "./Tooltip";
 import DataTable, { type Column } from "./DataTable";
@@ -28,13 +28,6 @@ export type ChannelsView = "subscribed" | "discovery";
 
 export type ChannelStatusFilter = "all" | "needs_full" | "fully_synced" | "hidden";
 
-// Compact total-duration label for a whole channel (hours-scale, so H:MM:SS would be huge).
-function fmtTotalDuration(sec: number): string {
-  if (!sec) return "—";
-  const h = Math.round(sec / 3600);
-  return h >= 1 ? `${h.toLocaleString()} h` : `${Math.max(1, Math.round(sec / 60))} m`;
-}
-
 const STATUS_FILTERS: { id: ChannelStatusFilter; labelKey: string }[] = [
   { id: "all", labelKey: "channels.filters.all" },
   { id: "needs_full", labelKey: "channels.filters.needsFull" },
@@ -287,7 +280,7 @@ export default function Channels({
       nowrap: true,
       sortable: true,
       sortValue: (c) => c.total_duration_seconds,
-      render: (c) => <span className="text-muted tabular-nums">{fmtTotalDuration(c.total_duration_seconds)}</span>,
+      render: (c) => <span className="text-muted tabular-nums">{formatTotalHours(c.total_duration_seconds)}</span>,
     },
     {
       key: "types",

frontend/src/components/NotificationsPanel.tsx

@@ -19,7 +19,7 @@ import {
   type VideoHiddenMeta,
   type VideoWatchedMeta,
 } from "../lib/notifications";
-import { channelYouTubeUrl } from "../lib/format";
+import { channelYouTubeUrl, relativeFromMs, relativeTime } from "../lib/format";
 import type { Page } from "../lib/urlState";
 import { LEVEL_STYLE } from "./Toaster";
 
@@ -29,22 +29,6 @@ import { LEVEL_STYLE } from "./Toaster";
 // there's one indicator and one place to look. Transient toasts still pop via the Toaster.
 const POLL_MS = 8000;
 
-function relativeTime(iso: string | null, t: (k: string, o?: any) => string): string {
-  if (!iso) return "";
-  return relativeFromMs(new Date(iso).getTime(), t);
-}
-
-function relativeFromMs(ms: number, t: (k: string, o?: any) => string): string {
-  const secs = Math.max(0, Math.round((Date.now() - ms) / 1000));
-  // Reuse the bell's relative-time strings (notifications.time.*) — same format, no dupes.
-  if (secs < 60) return t("notifications.time.justNow");
-  const mins = Math.round(secs / 60);
-  if (mins < 60) return t("notifications.time.minutes", { count: mins });
-  const hours = Math.round(mins / 60);
-  if (hours < 24) return t("notifications.time.hours", { count: hours });
-  return t("notifications.time.days", { count: Math.round(hours / 24) });
-}
-
 export default function NotificationsPanel({
   filters,
   setFilters,
@@ -253,7 +237,7 @@ function NotificationRow({
         <div className="flex items-baseline gap-2">
           <span className="font-medium text-sm">{title}</span>
           <span className="text-[11px] text-muted shrink-0">
-            {relativeTime(n.created_at, t)}
+            {relativeTime(n.created_at)}
           </span>
         </div>
         {body && <div className="text-sm text-muted mt-0.5">{body}</div>}
@@ -338,7 +322,7 @@ function ClientActivityRow({
         {n.title && <div className="text-sm font-semibold">{n.title}</div>}
         <div className="text-sm break-words">{n.message}</div>
         <div className="flex items-center gap-2 mt-0.5">
-          <span className="text-[11px] text-muted">{relativeFromMs(n.ts, t)}</span>
+          <span className="text-[11px] text-muted">{relativeFromMs(n.ts)}</span>
           {needsAction && (
             <span className="text-[10px] uppercase tracking-wide font-semibold text-accent">
               {t("notifications.actionNeeded")}

frontend/src/components/Scheduler.tsx

@@ -1,5 +1,6 @@
 import { useEffect, useState } from "react";
 import { useTranslation } from "react-i18next";
+import i18n from "../i18n";
 import { useMutation, useQueryClient } from "@tanstack/react-query";
 import {
   Activity,
@@ -31,7 +32,7 @@ function secsUntil(iso: string | null): number | null {
 }
 
 function fmtCountdown(s: number): string {
-  if (s <= 0) return "now";
+  if (s <= 0) return i18n.t("time.eta.now");
   if (s < 60) return `${s}s`;
   const m = Math.floor(s / 60);
   if (m < 60) return `${m}m ${s % 60}s`;

frontend/src/i18n/locales/de/notifications.json

@@ -11,11 +11,5 @@
   "openInManager": "Kanalverwaltung",
   "openOnYouTube": "Auf YouTube öffnen",
   "unhidden": "Eingeblendet „{{title}}”",
-  "unwatched": "Als nicht angesehen markiert „{{title}}”",
-  "time": {
-    "justNow": "gerade eben",
-    "minutes": "vor {{count}} Min.",
-    "hours": "vor {{count}} Std.",
-    "days": "vor {{count}} T."
-  }
+  "unwatched": "Als nicht angesehen markiert „{{title}}”"
 }

frontend/src/i18n/locales/de/time.json

@@ -6,5 +6,14 @@
   "daysAgo": "vor {{count}} T.",
   "weeksAgo": "vor {{count}} Wo.",
   "monthsAgo": "vor {{count}} Mon.",
-  "yearsAgo": "vor {{count}} J."
+  "yearsAgo": "vor {{count}} J.",
+  "eta": {
+    "now": "jetzt",
+    "done": "fertig",
+    "lessThanHour": "< 1 Stunde",
+    "hours_one": "~{{count}} Stunde",
+    "hours_other": "~{{count}} Stunden",
+    "days_one": "~{{count}} Tag",
+    "days_other": "~{{count}} Tage"
+  }
 }

frontend/src/i18n/locales/en/notifications.json

@@ -11,11 +11,5 @@
   "openInManager": "Channel manager",
   "openOnYouTube": "Open on YouTube",
   "unhidden": "Unhidden “{{title}}”",
-  "unwatched": "Unwatched “{{title}}”",
-  "time": {
-    "justNow": "just now",
-    "minutes": "{{count}}m ago",
-    "hours": "{{count}}h ago",
-    "days": "{{count}}d ago"
-  }
+  "unwatched": "Unwatched “{{title}}”"
 }

frontend/src/i18n/locales/en/time.json

@@ -6,5 +6,14 @@
   "daysAgo": "{{count}}d ago",
   "weeksAgo": "{{count}} wk ago",
   "monthsAgo": "{{count}} mo ago",
-  "yearsAgo": "{{count}} yr ago"
+  "yearsAgo": "{{count}} yr ago",
+  "eta": {
+    "now": "now",
+    "done": "done",
+    "lessThanHour": "< 1 hour",
+    "hours_one": "~{{count}} hour",
+    "hours_other": "~{{count}} hours",
+    "days_one": "~{{count}} day",
+    "days_other": "~{{count}} days"
+  }
 }

frontend/src/i18n/locales/hu/notifications.json

@@ -11,11 +11,5 @@
   "openInManager": "Csatornakezelő",
   "openOnYouTube": "Megnyitás a YouTube-on",
   "unhidden": "Megjelenítve: „{{title}}”",
-  "unwatched": "Megtekintés visszavonva: „{{title}}”",
-  "time": {
-    "justNow": "az imént",
-    "minutes": "{{count}} perce",
-    "hours": "{{count}} órája",
-    "days": "{{count}} napja"
-  }
+  "unwatched": "Megtekintés visszavonva: „{{title}}”"
 }

frontend/src/i18n/locales/hu/time.json

@@ -6,5 +6,14 @@
   "daysAgo": "{{count}} napja",
   "weeksAgo": "{{count}} hete",
   "monthsAgo": "{{count}} hónapja",
-  "yearsAgo": "{{count}} éve"
+  "yearsAgo": "{{count}} éve",
+  "eta": {
+    "now": "most",
+    "done": "kész",
+    "lessThanHour": "< 1 óra",
+    "hours_one": "~{{count}} óra",
+    "hours_other": "~{{count}} óra",
+    "days_one": "~{{count}} nap",
+    "days_other": "~{{count}} nap"
+  }
 }

frontend/src/lib/format.ts

@@ -2,8 +2,14 @@ import i18n from "../i18n";
 
 export function relativeTime(iso: string | null): string {
   if (!iso) return "";
-  const then = new Date(iso).getTime();
-  const secs = Math.max(0, (Date.now() - then) / 1000);
+  return relativeFromMs(new Date(iso).getTime());
+}
+
+/** Relative-time label from an epoch-millis timestamp (the ms-based half of relativeTime, for
+ * client-side notifications whose timestamps are already numbers). One implementation, one
+ * set of `time.*` strings — shared instead of re-implemented per component. */
+export function relativeFromMs(ms: number): string {
+  const secs = Math.max(0, (Date.now() - ms) / 1000);
   const units: [number, string][] = [
     [60, "time.secondsAgo"],
     [3600, "time.minutesAgo"],
@@ -51,17 +57,21 @@ export function quotaActionLabel(action: string): string {
   return i18n.t(`quotaActions.${action}`, { defaultValue: action });
 }
 
-/** Coarse, human ETA for a remaining duration in seconds ("~3 hours", "~2 days"). */
+/** Coarse, human ETA for a remaining duration in seconds ("~3 hours", "~2 days"). Translated
+ * via the `time.eta.*` keys (was hardcoded English, violating the trilingual rule). */
 export function formatEta(seconds: number): string {
-  if (seconds <= 0) return "done";
+  if (seconds <= 0) return i18n.t("time.eta.done");
   const hours = seconds / 3600;
-  if (hours < 1) return "< 1 hour";
-  if (hours < 24) {
-    const h = Math.round(hours);
-    return `~${h} hour${h === 1 ? "" : "s"}`;
-  }
-  const d = Math.round(hours / 24);
-  return `~${d} day${d === 1 ? "" : "s"}`;
+  if (hours < 1) return i18n.t("time.eta.lessThanHour");
+  if (hours < 24) return i18n.t("time.eta.hours", { count: Math.round(hours) });
+  return i18n.t("time.eta.days", { count: Math.round(hours / 24) });
+}
+
+/** Compact whole-channel total length ("12 h", "45 m"), hours-scale so H:MM:SS isn't huge. */
+export function formatTotalHours(sec: number): string {
+  if (!sec) return "—";
+  const h = Math.round(sec / 3600);
+  return h >= 1 ? `${h.toLocaleString()} h` : `${Math.max(1, Math.round(sec / 60))} m`;
 }
 
 export function formatViews(n: number | null): string {