Add SMS gating, TCPA terms agreement, and compose-before-send modal

- Three-tier SMS gate: platform kill-switch → admin force-disable → plan AllowSms → company opt-in
- CompanySmsAgreement entity records admin acceptance of TCPA terms with IP, user agent, and terms version
- SMS terms of service modal on Company Settings with versioned re-agreement (AppConstants.SmsTermsVersion)
- Dev redirect: non-production SMS routed to Twilio:DevRedirectPhone to protect real customer numbers
- Removed redundant Ready for Pickup SMS (Job Completed covers it)
- Role-based compose modal on job completion: Admin/Manager reviews and edits before send; ShopFloor auto-sends
- Send SMS button on job details for ad-hoc messages (Admin/Manager only)
- SendJobSmsAsync auto-appends STOP opt-out language if missing
- Migrations: AddSmsGating, AddCompanySmsAgreement

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

src/PowderCoating.Application/Interfaces/INotificationService.cs

@@ -23,8 +23,23 @@ public interface INotificationService
 
     /// <summary>
     /// Notify customer when a job is completed and ready for pickup.
+    /// When <paramref name="suppressSms"/> is true the SMS is skipped so an admin can review
+    /// the message via <see cref="RenderJobCompletedSmsAsync"/> before sending manually.
     /// </summary>
-    Task NotifyJobCompletedAsync(Job job);
+    Task NotifyJobCompletedAsync(Job job, bool suppressSms = false);
+
+    /// <summary>
+    /// Renders the job-completed SMS text for admin preview without sending it.
+    /// Returns null when SMS is not allowed for the company or the customer has not opted in.
+    /// </summary>
+    Task<string?> RenderJobCompletedSmsAsync(Job job);
+
+    /// <summary>
+    /// Sends a manually-composed SMS for a job (Admin/Manager compose-before-send path).
+    /// Appends "Reply STOP to opt out." if not already present, sends, and writes a NotificationLog row.
+    /// Returns (success, errorMessage).
+    /// </summary>
+    Task<(bool Success, string? Error)> SendJobSmsAsync(Job job, string message);
 
     /// <summary>
     /// Sends a welcome/confirmation SMS after staff records verbal SMS consent.