feat(GRO-600): extend reminder scheduler to send SMS alongside email

- Add SMS opt-in fields to clients schema (smsOptIn, smsConsentDate, smsOptOutDate, smsConsentText)
- Add channel column to reminderLogs with per-channel idempotency
- Create SMS service with Telnyx SDK integration and E.164 validation
- Update reminders service to conditionally send SMS to opted-in clients
- Add TCPA opt-out text to SMS reminders
- Graceful degradation: catch SMS errors without blocking email
- Fix: use clients.phone instead of non-existent clients.phoneE164
- Update clients route to expose SMS fields in API
- Add telnyx dependency to API package
- Create database migration 0028_sms_reminders

Co-Authored-By: Paperclip <noreply@paperclip.ing>

packages/db/src/factories.ts

@@ -71,6 +71,10 @@ export function buildClient(overrides: Partial<ClientRow> = {}): ClientRow {
     address: "1 Main St, Springfield, CA 90000",
     notes: null,
     emailOptOut: false,
+    smsOptIn: false,
+    smsConsentDate: null,
+    smsOptOutDate: null,
+    smsConsentText: null,
     stripeCustomerId: null,
     status: "active",
     disabledAt: null,