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.Core/Entities/Company.cs

@@ -123,6 +123,16 @@ public class Company : BaseEntity
     public byte[]? LogoData { get; set; }  // Legacy - kept for backward compatibility
     public string? LogoContentType { get; set; }  // Legacy - kept for backward compatibility
     public string? LogoFilePath { get; set; }  // Filesystem path: /media/{CompanyId}/company-logo.{ext}
+
+    // Kiosk
+    /// <summary>
+    /// Random token written to a long-lived HttpOnly cookie on the front-desk tablet when the
+    /// owner activates the kiosk. Kiosk routes validate this token against the cookie so the
+    /// tablet can serve the intake form without requiring a logged-in user.
+    /// Null = kiosk not activated. Regenerate to revoke the current device.
+    /// </summary>
+    public string? KioskActivationToken { get; set; }
+
     // Navigation Properties
     public virtual ICollection<ApplicationUser> Users { get; set; } = new List<ApplicationUser>();
     public virtual ICollection<Customer> Customers { get; set; } = new List<Customer>();

src/PowderCoating.Core/Entities/Invoice.cs

@@ -28,6 +28,13 @@ public class Invoice : BaseEntity
     public decimal GiftCertificateRedeemed { get; set; }   // Sum of gift certificate redemptions
     public decimal BalanceDue => Total - AmountPaid - CreditApplied - GiftCertificateRedeemed;
 
+    /// <summary>
+    /// Permanent public token for the customer-facing invoice view page (/invoice/{token}).
+    /// Generated when the invoice is first sent (regardless of Stripe status) and never expires.
+    /// Distinct from PaymentLinkToken which is Stripe-gated and expires in 5 days.
+    /// </summary>
+    public string? PublicViewToken { get; set; }
+
     // Online payments (Stripe Connect)
     public OnlinePaymentStatus OnlinePaymentStatus { get; set; } = OnlinePaymentStatus.NotApplicable;
     public string? PaymentLinkToken { get; set; }           // Signed token for /pay/{token}

src/PowderCoating.Core/Entities/KioskSession.cs

@@ -0,0 +1,51 @@
+using PowderCoating.Core.Enums;
+
+namespace PowderCoating.Core.Entities;
+
+/// <summary>
+/// Represents one customer self-service intake session — either completed on the front-desk tablet
+/// (InPerson) or via an emailed link the customer fills out on their own device (Remote).
+/// Sessions are tenant-scoped and soft-deletable. Load anonymous sessions with ignoreQueryFilters:true.
+/// </summary>
+public class KioskSession : BaseEntity
+{
+    /// <summary>URL-safe GUID used in all kiosk routes; unique across the table.</summary>
+    public Guid SessionToken { get; set; } = Guid.NewGuid();
+
+    public KioskSessionType SessionType { get; set; }
+    public KioskSessionStatus Status { get; set; } = KioskSessionStatus.Active;
+
+    // ── Step 1 — Contact ─────────────────────────────────────────────────────
+    public string CustomerFirstName { get; set; } = string.Empty;
+    public string CustomerLastName  { get; set; } = string.Empty;
+    public string CustomerPhone     { get; set; } = string.Empty;
+    public string CustomerEmail     { get; set; } = string.Empty;
+    public bool   IsReturningCustomer { get; set; }
+
+    // ── Step 2 — Job Description ──────────────────────────────────────────────
+    public string  JobDescription        { get; set; } = string.Empty;
+    public string? HowDidYouHearAboutUs  { get; set; }
+
+    // ── Step 3 — Terms & Consent ──────────────────────────────────────────────
+    public bool      AgreedToTerms        { get; set; }
+    public DateTime? AgreedToTermsAt      { get; set; }
+    /// <summary>Customer opted in to SMS order updates; sets Customer.NotifyBySms on submission.</summary>
+    public bool      SmsOptIn             { get; set; }
+    /// <summary>Base-64 PNG from signature_pad; null for Remote sessions (no drawn signature required).</summary>
+    public string?   SignatureDataBase64  { get; set; }
+
+    // ── Outcome ───────────────────────────────────────────────────────────────
+    public int?      LinkedCustomerId { get; set; }
+    public int?      LinkedJobId      { get; set; }
+    public DateTime? SubmittedAt      { get; set; }
+    /// <summary>Sessions auto-expire 2 h after creation (InPerson) or 48 h (Remote). ExpiresAt is set at creation.</summary>
+    public DateTime  ExpiresAt        { get; set; }
+
+    // ── Remote-only ───────────────────────────────────────────────────────────
+    public string?   RemoteLinkEmail   { get; set; }
+    public DateTime? RemoteLinkSentAt  { get; set; }
+
+    // ── Navigation ────────────────────────────────────────────────────────────
+    public virtual Customer? LinkedCustomer { get; set; }
+    public virtual Job?      LinkedJob      { get; set; }
+}