Redesign: Start/Stop buttons, locked settings, queue countdown, wb2 logo

- Replace tumbler with Start/Stop buttons (green/red)
- Lock settings form with <fieldset disabled> when auto-reply active
- Clear queue + reset fetch timer on settings save
- Show 'Очередь подгрузится через X сек.' countdown in queue section
- API /status returns next_fetch_seconds, queue_len, auto_reply_enabled
- Login: price 15₽/день, up to 144 replies/day, wb2 logo, promo panel 25% width
- Replace wb.png → wb2.png across all templates

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

templates/register.html

@@ -10,7 +10,7 @@
     <div class="auth-shell">
         <section class="auth-card">
             <div class="auth-kicker">
-                <img src="{{ url_for('static', filename='wb.png') }}" class="auth-kicker-logo-img" alt="WB">
+                <img src="{{ url_for('static', filename='wb2.png') }}" class="auth-kicker-logo-img" alt="WB">
                 <span class="auth-kicker-text">Wildberries Feedback</span>
             </div>
             <h1>Запрос доступа</h1>