refactor(ui): one rule for resettable, role key and display name; an honest reset label

The card menu's reset read 'Clear watch progress' but also un-hides and un-watches; it now says so.
The resettable rule, the demo-first role key and the display-name fallback each lived in several
components tied by comments; they are shared helpers now, and the menu reuses the card's own
strings instead of duplicate keys.

frontend/src/components/ComfortPinMenu.tsx

@@ -2,6 +2,7 @@ import { useTranslation } from "react-i18next";
 import { Bookmark, BookmarkX, Check, Eye, EyeOff, RotateCcw, Undo2 } from "lucide-react";
 
 import { type PlexCard, type Video, type VideoStatus } from "../lib/api";
+import { isResettable } from "../lib/api/feed";
 import { pinPlex, pinVideo, useComfortPin, type PinTarget } from "./comfortPin";
 import { type ActionMenuItem } from "./ui/ActionMenu";
 import { ContextMenu } from "./ui/ContextMenu";
@@ -75,24 +76,23 @@ export function FeedVideoMenu({
             }
           : {
               id: "watched",
-              label: t("card.menu.markWatched"),
+              label: t("card.markWatched"),
               icon: <Check className={icon} />,
               onSelect: () => onState(v.id, "watched"),
             },
         {
           id: "save",
-          label: v.saved ? t("card.menu.unsave") : t("card.menu.save"),
+          label: v.saved ? t("card.menu.unsave") : t("card.saveForLater"),
           icon: v.saved ? <BookmarkX className={icon} /> : <Bookmark className={icon} />,
           onSelect: () => onToggleSave(v.id, !v.saved),
         },
         {
           id: "hide",
-          label: v.status === "hidden" ? t("card.menu.unhide") : t("card.menu.hide"),
+          label: v.status === "hidden" ? t("card.unhide") : t("card.hide"),
           icon: v.status === "hidden" ? <Eye className={icon} /> : <EyeOff className={icon} />,
           onSelect: () => onState(v.id, v.status === "hidden" ? "new" : "hidden"),
         },
-        // The card offers the reset only on a card that has something to reset; so does this.
-        ...(v.status !== "new" || v.position_seconds > 0
+        ...(isResettable(v)
           ? [
               {
                 id: "reset",