feat: add per-org SMS wallet with adm panel and header credit

Bill all platform SMS (including OTP), allow negative balance with manual/auto cutoffs, and support own-panel bypass without wallet debit.

apps/api/src/app.module.ts

@@ -53,6 +53,7 @@ import { GamificationModule } from './gamification/gamification.module';
 import { DeletionsModule } from './deletions/deletions.module';
 import { OutboundSmsModule } from './outbound-sms/outbound-sms.module';
 import { BehaviorModule } from './behavior/behavior.module';
+import { SmsBillingModule } from './sms-billing/sms-billing.module';
 
 @Module({
   imports: [
@@ -63,6 +64,7 @@ import { BehaviorModule } from './behavior/behavior.module';
     ScheduleModule.forRoot(),
     AiModule,
     PrismaModule,
+    SmsBillingModule,
     OutboundSmsModule,
     StorageModule,
     HealthModule,