feat(auth): implement Auth module with register, login, JWT, guards, and CQRS

- Add RefreshToken and OAuthAccount models to Prisma schema
- Implement clean architecture: domain (entities, VOs, events, repo interfaces),
  infrastructure (Prisma repos, Passport strategies, token service),
  application (CQRS command/query handlers), presentation (controller, guards, DTOs)
- Endpoints: POST /auth/register, /auth/login, /auth/refresh, GET /auth/profile,
  GET /auth/profile/agent, PATCH /auth/kyc
- JWT access + refresh token rotation with family-based revocation
- Role-based guards (BUYER, SELLER, AGENT, ADMIN)
- 16 unit tests (value objects, entity) + integration test suite
- All 80 tests passing, clean TypeScript build

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

apps/api/src/modules/auth/presentation/guards/roles.guard.ts

@@ -0,0 +1,23 @@
+import { Injectable, type CanActivate, type ExecutionContext } from '@nestjs/common';
+import { Reflector } from '@nestjs/core';
+import { type UserRole } from '@prisma/client';
+import { ROLES_KEY } from '../decorators/roles.decorator';
+
+@Injectable()
+export class RolesGuard implements CanActivate {
+  constructor(private readonly reflector: Reflector) {}
+
+  canActivate(context: ExecutionContext): boolean {
+    const requiredRoles = this.reflector.getAllAndOverride<UserRole[]>(ROLES_KEY, [
+      context.getHandler(),
+      context.getClass(),
+    ]);
+
+    if (!requiredRoles || requiredRoles.length === 0) {
+      return true;
+    }
+
+    const { user } = context.switchToHttp().getRequest();
+    return requiredRoles.includes(user?.role);
+  }
+}