Add invoice SMS notifications and customer intake kiosk

Invoice SMS:
- Send Invoice modal now prompts Email/SMS/Both based on customer contact data
- New /invoice/{token} customer-facing view page with full line items and pay button
- PublicViewToken (permanent) added to Invoice; separate from expiring PaymentLinkToken
- InvoiceSent SMS default template added; customizable via Notification Templates settings
- {{viewUrl}} placeholder documented in template editor

Customer Intake Kiosk:
- Tablet kiosk flow: Contact → Job → Terms/Signature → Confirmation
- Remote link mode for off-site customers (lighter form, no signature)
- KioskHub (AllowAnonymous SignalR) for staff-to-tablet push without login
- Staff activates tablet via cookie; sends remote link manually
- Submitted sessions create Customer + Job automatically; fires in-app notification

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

src/PowderCoating.Infrastructure/Services/NotificationService.cs

@@ -621,7 +621,7 @@ public class NotificationService : INotificationService
     /// (the <paramref name="paymentUrl"/> parameter). Without a payment URL the email is a
     /// standard "here is your invoice" message with no payment CTA.
     /// </summary>
-    public async Task NotifyInvoiceSentAsync(Invoice invoice, byte[]? pdfAttachment = null, string? pdfFilename = null, string? paymentUrl = null, string? overrideEmail = null)
+    public async Task NotifyInvoiceSentAsync(Invoice invoice, byte[]? pdfAttachment = null, string? pdfFilename = null, string? paymentUrl = null, string? overrideEmail = null, bool sendSms = false, string? viewUrl = null)
     {
         try
         {
@@ -705,6 +705,50 @@ public class NotificationService : INotificationService
                 await WriteLog(SkippedLog(NotificationChannel.Email, NotificationType.InvoiceSent,
                     customerName, string.Join(", ", invoiceEmails), invoice.CompanyId, customerId: customer.Id, invoiceId: invoice.Id));
             }
+
+            // SMS — only when explicitly requested by staff (sendSms=true), customer has opted in,
+            // and the company's SMS is active. Uses viewUrl (permanent) so customer can see the full
+            // invoice; paymentUrl (expiring Stripe link) is surfaced on the view page itself.
+            if (sendSms)
+            {
+                var smsAllowed = await IsSmsAllowedForCompanyAsync(company);
+                var smsPhone = customer.MobilePhone ?? customer.Phone;
+                if (smsAllowed && customer.NotifyBySms && !string.IsNullOrWhiteSpace(smsPhone))
+                {
+                    var urlForSms = viewUrl ?? paymentUrl ?? string.Empty;
+                    var values = new Dictionary<string, string>
+                    {
+                        ["companyName"]    = companyName,
+                        ["invoiceNumber"]  = invoice.InvoiceNumber,
+                        ["invoiceTotal"]   = invoice.Total.ToString("C"),
+                        ["viewUrl"]        = urlForSms
+                    };
+
+                    var message = await GetRenderedSmsAsync(invoice.CompanyId, NotificationType.InvoiceSent, values,
+                        $"{companyName}: Invoice {invoice.InvoiceNumber} for {invoice.Total:C} is ready. View your invoice: {urlForSms} Reply STOP to opt out.");
+                    var (smsSent, smsError) = await _smsService.SendSmsAsync(smsPhone, message);
+
+                    await WriteLog(new NotificationLog
+                    {
+                        Channel = NotificationChannel.Sms,
+                        NotificationType = NotificationType.InvoiceSent,
+                        Status = smsSent ? NotificationStatus.Sent : NotificationStatus.Failed,
+                        RecipientName = customerName,
+                        Recipient = smsPhone,
+                        Message = message,
+                        ErrorMessage = smsError,
+                        SentAt = DateTime.UtcNow,
+                        CustomerId = customer.Id,
+                        InvoiceId = invoice.Id,
+                        CompanyId = invoice.CompanyId
+                    });
+                }
+                else if (!string.IsNullOrWhiteSpace(smsPhone))
+                {
+                    await WriteLog(SkippedLog(NotificationChannel.Sms, NotificationType.InvoiceSent,
+                        customerName, smsPhone, invoice.CompanyId, customerId: customer.Id, invoiceId: invoice.Id));
+                }
+            }
         }
         catch (Exception ex)
         {
@@ -1153,6 +1197,10 @@ public class NotificationService : INotificationService
                     "Invoice {{invoiceNumber}} from {{companyName}}",
                     "<p>Dear {{customerName}},</p><p>Please find your invoice <strong>{{invoiceNumber}}</strong> for <strong>{{invoiceTotal}}</strong> attached.{{invoiceDueDate}}</p><p>Thank you for your business with {{companyName}}.</p>"
                 ),
+                [(NotificationType.InvoiceSent, NotificationChannel.Sms)] = (
+                    null,
+                    "{{companyName}}: Invoice {{invoiceNumber}} for {{invoiceTotal}} is ready. View your invoice: {{viewUrl}} Reply STOP to opt out."
+                ),
                 [(NotificationType.PaymentReceived, NotificationChannel.Email)] = (
                     "Payment Received — Invoice {{invoiceNumber}}",
                     "<p>Dear {{customerName}},</p><p>We have received your payment of <strong>{{paymentAmount}}</strong> on {{paymentDate}} for invoice <strong>{{invoiceNumber}}</strong>.{{balanceDue}}</p><p>Thank you for your business with {{companyName}}.</p>"