Fix notification bell, SMS consent kiosk flow, and button alignment

Notification bell:
- Bell now polls /InAppNotifications/Recent every 60s as a SignalR fallback
- Bell dropdown refresh on open so count is always current when staff looks at it

SMS consent → kiosk flow:
- Staff clicks "Get SMS Consent" on Customer Details → AJAX POST to
  /Kiosk/PushSmsConsent stores customer in IMemoryCache (10 min TTL)
- Kiosk PollSession returns smsConsentPending + customerId so tablet navigates
  to /Kiosk/SmsConsent/{customerId} automatically
- Customer reads TCPA consent on tablet, taps I Agree or No Thanks
- On agree: NotifyBySms/SmsConsentedAt/SmsConsentMethod set; in-app notification
  fires; cache cleared; tablet returns to Welcome
- Removed Customers/SmsConsent (staff-browser version); moved view to Kiosk/

Button alignment:
- kiosk.css: added display:flex + align-items:center + justify-content:center to
  all kiosk body buttons so content is centred vertically in tall button outlines

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

src/PowderCoating.Web/Views/Shared/_Layout.cshtml

@@ -2101,8 +2101,14 @@
                     });
                 });
 
-                // Load on page ready
-                document.addEventListener('DOMContentLoaded', load);
+                // Load on page ready and refresh when dropdown is opened
+                document.addEventListener('DOMContentLoaded', () => {
+                    load();
+                    btn?.addEventListener('show.bs.dropdown', load);
+                });
+
+                // Fallback poll every 60 s in case SignalR misses a push
+                setInterval(load, 60_000);
 
                 return { addItem, incrementBadge, markAllRead, openDetail, markRead };
             })();