feat(templates): T6 controller + DTOs + module wiring

POST /v1/templates/send (render→queue) and /preview (render only). OPA-gated in
the sender: iios.template.send, and iios.template.send.inline for ad-hoc HTML
(arbitrary markup to a customer is riskier than a reviewed stored template).
Scope resolved from the caller's principal. TemplateModule registered in AppModule.

Verified over HTTP against a local boot: preview + send of the seeded
payment.receipt (SENT via sandbox, provenance persisted), XSS name escaped,
idempotent replay → 1 row, unknown key 404, bad channel/no-source/no-auth 400.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packages/iios-service/src/templates/template.module.ts

@@ -0,0 +1,21 @@
+import { Module } from '@nestjs/common';
+import { AdaptersModule } from '../adapters/adapters.module';
+import { TemplateRepository } from './template.repository';
+import { TemplateService } from './template.service';
+import { TemplatedSender } from './templated-sender';
+import { TemplateSeeder } from './template.seeder';
+import { TemplateController } from './template.controller';
+
+/**
+ * Reusable message-template module: render a stored/inline template → hand it to the existing
+ * outbound pipeline (via AdaptersModule's OutboundService). Content lives here; delivery stays in
+ * the outbound/capability layers. SessionVerifier, ActorResolver (IdentityModule) and PLATFORM_PORTS
+ * (PlatformModule) are global.
+ */
+@Module({
+  imports: [AdaptersModule],
+  controllers: [TemplateController],
+  providers: [TemplateRepository, TemplateService, TemplatedSender, TemplateSeeder],
+  exports: [TemplateService, TemplatedSender],
+})
+export class TemplateModule {}