feat: bulk send templates via csv (#1578)

Implements a bulk send feature allowing users to upload a CSV file to
create multiple documents from a template. Includes CSV template
generation, background processing, and email notifications.

packages/lib/jobs/definitions/internal/bulk-send-template.ts

@@ -0,0 +1,37 @@
+import { z } from 'zod';
+
+import { ZRequestMetadataSchema } from '../../../universal/extract-request-metadata';
+import { type JobDefinition } from '../../client/_internal/job';
+
+const BULK_SEND_TEMPLATE_JOB_DEFINITION_ID = 'internal.bulk-send-template';
+
+const BULK_SEND_TEMPLATE_JOB_DEFINITION_SCHEMA = z.object({
+  userId: z.number(),
+  teamId: z.number().optional(),
+  templateId: z.number(),
+  csvContent: z.string(),
+  sendImmediately: z.boolean(),
+  requestMetadata: ZRequestMetadataSchema.optional(),
+});
+
+export type TBulkSendTemplateJobDefinition = z.infer<
+  typeof BULK_SEND_TEMPLATE_JOB_DEFINITION_SCHEMA
+>;
+
+export const BULK_SEND_TEMPLATE_JOB_DEFINITION = {
+  id: BULK_SEND_TEMPLATE_JOB_DEFINITION_ID,
+  name: 'Bulk Send Template',
+  version: '1.0.0',
+  trigger: {
+    name: BULK_SEND_TEMPLATE_JOB_DEFINITION_ID,
+    schema: BULK_SEND_TEMPLATE_JOB_DEFINITION_SCHEMA,
+  },
+  handler: async ({ payload, io }) => {
+    const handler = await import('./bulk-send-template.handler');
+
+    await handler.run({ payload, io });
+  },
+} as const satisfies JobDefinition<
+  typeof BULK_SEND_TEMPLATE_JOB_DEFINITION_ID,
+  TBulkSendTemplateJobDefinition
+>;