feat(points): balance, history and shop page

Add /points page with wallet balance, shop grouped by slot and ledger
history with game names. The wallet loads once in PreferencesContext after
login, so the header shows a balance chip and the link. Premium accents
gold and teal override the free accent while equipped. German and English.

src/components/AppHeader.jsx

@@ -1,7 +1,7 @@
 import {useEffect, useState} from 'react';
 import {Link, NavLink, useLocation, useNavigate} from 'react-router-dom';
 import {useTranslation} from 'react-i18next';
-import {ChartColumn, Dices, Eye, Languages, LayoutDashboard, Library, LogOut, Megaphone, Moon, Newspaper, Settings, Shield, Sun} from 'lucide-react';
+import {ChartColumn, Coins, Dices, Eye, Languages, LayoutDashboard, Library, LogOut, Megaphone, Moon, Newspaper, Settings, Shield, Sun} from 'lucide-react';
 import {toast} from 'sonner';
 
 import {Badge} from '@/components/ui/badge';
@@ -43,7 +43,7 @@ const navLinkClass = (isActive) => cn(
 
 export default function AppHeader({isAuthenticated, onLogout}) {
     const {t, i18n} = useTranslation();
-    const {isDarkMode, setDarkMode, setLanguage} = usePreferences();
+    const {isDarkMode, setDarkMode, setLanguage, wallet} = usePreferences();
     const {pathname} = useLocation();
     const steamProfile = useSteamProfile(isAuthenticated);
     const currentUser = useCurrentUser(isAuthenticated);
@@ -126,6 +126,11 @@ export default function AppHeader({isAuthenticated, onLogout}) {
                     {isAuthenticated && viewingAs && (
                         <Badge variant="secondary" className="mr-1">{t('NAV.VIEW_AS.BADGE', {role: t(`ROLES.${viewingAs}`)})}</Badge>
                     )}
+                    {isAuthenticated && wallet && (
+                        <Button asChild variant="ghost" size="sm" title={t('POINTS.TITLE')}>
+                            <Link to="/points"><Coins className="text-primary"/><span className="tabular-nums">{wallet.balance}</span></Link>
+                        </Button>
+                    )}
                     {isAuthenticated ? (
                         <DropdownMenu onOpenChange={(open) => open && setMenuOpenings((count) => count + 1)}>
                             <DropdownMenuTrigger asChild>
@@ -144,6 +149,9 @@ export default function AppHeader({isAuthenticated, onLogout}) {
                                 <DropdownMenuItem asChild>
                                     <Link to="/settings"><Settings/>{t('NAV.SETTINGS')}</Link>
                                 </DropdownMenuItem>
+                                <DropdownMenuItem asChild>
+                                    <Link to="/points"><Coins/>{t('NAV.POINTS')}</Link>
+                                </DropdownMenuItem>
                                 <DropdownMenuItem asChild>
                                     <Link to="/whats-new"><Newspaper/>{t('NAV.WHATS_NEW')}</Link>
                                 </DropdownMenuItem>