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.Web/appsettings.json

@@ -48,9 +48,10 @@
     "FromName": "Powder Coating App Staff"
   },
   "Twilio": {
-    "AccountSid": "your-account-sid-here",
-    "AuthToken": "your-auth-token-here",
-    "FromNumber": "+1XXXXXXXXXX"
+    "AccountSid": "SK45bb87a7645d34c9227ea20faccad642",
+    "AuthToken": " f262409674753f285b1c8184785c270e",
+    "FromNumber": "+18664883595",
+    "DevRedirectPhone": ""
   },
   "Stripe": {
     "SecretKey": "sk_test_51TM6ukDedBup3CZU5TLbLhbBZDuBYwwygoc58JZwIrYQ2SyhKPUFcbHkFV1Q5osqkIEPt3XkwgsuinSJbY58GLx300l7z2lvqg",