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/wwwroot/js/customer-details.js

@@ -0,0 +1,19 @@
+"use strict";
+
+async function pushSmsConsent(customerId) {
+    const tok = document.querySelector('input[name="__RequestVerificationToken"]')?.value ?? '';
+    try {
+        const res  = await fetch(`/Kiosk/PushSmsConsent?customerId=${customerId}`, {
+            method:  'POST',
+            headers: { 'RequestVerificationToken': tok }
+        });
+        const data = await res.json();
+        if (data.success) {
+            toastr.success('Consent form sent to the kiosk tablet — hand it to the customer.', 'Sent to Kiosk');
+        } else {
+            toastr.warning(data.message || 'Could not send consent to kiosk.');
+        }
+    } catch {
+        toastr.error('An error occurred. Please try again.');
+    }
+}