feat(marketing-pages): sendWelcomeEmail job + handler enqueues it

sendWelcomeEmailJob takes IMailerService, validates the typed input
(userId + email), and delegates to mailer.sendWelcome. The
onAuthUserSignedUpHandler now takes IJobQueue and enqueues
"marketing-pages.send-welcome-email" with the event payload.

Both binders bind a RecordingMailerService at the IMailerService
symbol (production placeholder until a real adapter ships) and pass
mailer / queue into the wrapped factories. Dev-seed additionally
queue.register()s the slug so the in-memory queue dispatches via
the wrapped job; production relies on the generated Payload event-task
to resolve the wrapped handler from the container.

packages/marketing-pages/src/jobs/send-welcome-email.job.test.ts

@@ -0,0 +1,37 @@
+// packages/marketing-pages/src/jobs/send-welcome-email.job.test.ts
+import { describe, it, expect } from "vitest";
+import { sendWelcomeEmailJob, sendWelcomeEmailInputSchema } from "@/jobs/send-welcome-email.job";
+import { RecordingMailerService } from "@/infrastructure/services/recording-mailer.service";
+
+describe("sendWelcomeEmailJob", () => {
+  it("rejects unknown input fields", async () => {
+    const mailer = new RecordingMailerService();
+    const job = sendWelcomeEmailJob(mailer);
+    await expect(job({ unexpectedField: 1 } as never)).rejects.toThrow();
+  });
+
+  it("rejects input missing required fields", async () => {
+    const mailer = new RecordingMailerService();
+    const job = sendWelcomeEmailJob(mailer);
+    await expect(job({ userId: "u1" } as never)).rejects.toThrow();
+  });
+
+  it("rejects invalid email", async () => {
+    const mailer = new RecordingMailerService();
+    const job = sendWelcomeEmailJob(mailer);
+    await expect(
+      job({ userId: "u1", email: "not-an-email" }),
+    ).rejects.toThrow();
+  });
+
+  it("sends a welcome email via the mailer on valid input", async () => {
+    const mailer = new RecordingMailerService();
+    const job = sendWelcomeEmailJob(mailer);
+    await job({ userId: "u1", email: "u1@example.com" });
+    expect(mailer.sent).toEqual([{ userId: "u1", email: "u1@example.com" }]);
+  });
+
+  it("references its input schema", () => {
+    expect(sendWelcomeEmailInputSchema).toBeDefined();
+  });
+});

packages/marketing-pages/src/jobs/send-welcome-email.job.ts

@@ -0,0 +1,20 @@
+// packages/marketing-pages/src/jobs/send-welcome-email.job.ts
+import { z } from "zod";
+import type { IMailerService } from "../application/services/mailer.service.interface";
+
+export const sendWelcomeEmailInputSchema = z
+  .object({
+    userId: z.string(),
+    email: z.string().email(),
+  })
+  .strict();
+
+export type SendWelcomeEmailInput = z.infer<typeof sendWelcomeEmailInputSchema>;
+export type ISendWelcomeEmailJob = ReturnType<typeof sendWelcomeEmailJob>;
+
+export const sendWelcomeEmailJob =
+  (mailer: IMailerService) =>
+  async (input: SendWelcomeEmailInput): Promise<void> => {
+    sendWelcomeEmailInputSchema.parse(input);
+    await mailer.sendWelcome(input.userId, input.email);
+  };