feat(platform): Sistema > Permissões (catálogo RBAC, só leitura)

GET /platform/roles novo — lista as 4 roles do sistema com as permissions
de cada uma, mais o catálogo completo de permissions. roles/permissions
não têm RLS (catálogo global do seed); só leitura, RBAC é system-defined,
sem UI de criar role customizada ainda.

Frontend: /platform/sistema/permissoes, um card por role + tabela do
catálogo completo. Testado ponta a ponta: as 4 roles reais (platform_super_admin
33 permissions, tenant_admin 30, supervisor 17, agent 2) corretas. Smoke
test nas 19 telas do tenant + 9 telas platform, todas 200.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BFaBaBSQGhyXGEgtTYZGV8

apps/api/src/platform/platform.module.ts

@@ -3,8 +3,15 @@ import { PlatformOverviewController } from "./platform-overview.controller";
 import { PlatformUsersController } from "./platform-users.controller";
 import { PlatformAuditController } from "./platform-audit.controller";
 import { PlatformHealthController } from "./platform-health.controller";
+import { PlatformRolesController } from "./platform-roles.controller";
 
 @Module({
-  controllers: [PlatformOverviewController, PlatformUsersController, PlatformAuditController, PlatformHealthController],
+  controllers: [
+    PlatformOverviewController,
+    PlatformUsersController,
+    PlatformAuditController,
+    PlatformHealthController,
+    PlatformRolesController,
+  ],
 })
 export class PlatformModule {}