feat(dashboard): new layout with sync button and top 5 most played

Remove the placeholder tiles and the settings tile, fix the mobile header width. iconUrl/formatPlaytime move to utils/games.js (599 min now shows 10h, not 10.0h), and the sync button logic to the useForceSync hook shared with the library.

src/pages/GameDetail.jsx

@@ -1,17 +1,7 @@
 import {useEffect, useMemo, useState} from 'react';
 import {Link, useNavigate, useParams} from 'react-router-dom';
 import {useTranslation} from 'react-i18next';
-
-const iconUrl = (appid, hash) =>
-    hash
-        ? `https://cdn.cloudflare.steamstatic.com/steamcommunity/public/images/apps/${appid}/${hash}.jpg`
-        : null;
-
-const formatPlaytime = (minutes) => {
-    if (!minutes || minutes <= 0) return '0h';
-    const hours = minutes / 60;
-    return hours >= 10 ? `${Math.round(hours)}h` : `${hours.toFixed(1)}h`;
-};
+import {formatPlaytime, iconUrl} from '../utils/games.js';
 
 const formatUnlockedAt = (instant, locale) => {
     if (!instant) return '';