feat(onboarding): remove dead ends for new users (#55)

Registration shows the address used and can start over.
Confirm page says an admin approves; no login link.
Welcome puts next steps first; Steam link returns to the dashboard.
Dashboard and library explain an empty or private library.
First sync shows queued, polls slower up to 10 min, then a calm text.
Login: simple checks, resend offer after 401, password toggles.
Only a real expired link counts as invalid; typed passwords stay.
Default language follows the browser; texts are platform-neutral.

src/components/DashboardWelcomeCard.jsx

@@ -15,7 +15,7 @@ import {useCurrentUserContext} from '../context/CurrentUserContext.jsx';
 import {bannerEffect, lookClass} from '../utils/rewards.js';
 
 // canSync: a Steam ID or a PlayStation link; the sync controls follow it, the Steam ID badge only the Steam ID.
-export default function DashboardWelcomeCard({bannerAppid, avatarUrl, sync, forceSync, canSync, editing, onCustomize, equipped}) {
+export default function DashboardWelcomeCard({bannerAppid, avatarUrl, sync, forceSync, canSync, editing, onCustomize, equipped, returning}) {
     const {t} = useTranslation();
     const {user: userData} = useCurrentUserContext();
     const hasSteamId = !!userData?.steamId;
@@ -36,7 +36,7 @@ export default function DashboardWelcomeCard({bannerAppid, avatarUrl, sync, forc
                     </span>
                 )}
                 <div className="min-w-0 flex-1">
-                    <p className="text-sm font-medium text-muted-foreground">{t('DASHBOARD.WELCOME_BACK')}</p>
+                    <p className="text-sm font-medium text-muted-foreground">{t(returning ? 'DASHBOARD.WELCOME_BACK' : 'DASHBOARD.WELCOME')}</p>
                     <h1 className="@container mt-1 text-3xl md:text-4xl font-bold tracking-tight">
                         <FitText text={[t('DASHBOARD.HELLO'), userData?.displayName ?? userData?.email?.split('@')[0], '👋'].filter(Boolean).join(' ')}/>
                     </h1>
@@ -61,6 +61,7 @@ export default function DashboardWelcomeCard({bannerAppid, avatarUrl, sync, forc
                             status={sync.status}
                             lastSyncedAt={sync.lastSyncedAt}
                             isRunning={sync.isRunning}
+                            queued={sync.queued}
                             stale={sync.stale}
                         />
                         <Button onClick={forceSync.trigger} disabled={syncBusy}>