Add sendEmail workflow with immediate processing option

- Create sendEmailWorkflow as a Payload workflow alternative to task
- Add processImmediately option (disabled by default) to send emails immediately
- Expose processEmailItem method in MailingService for individual email processing
- Add comprehensive input schema with conditional fields
- Update plugin to register both tasks and workflows
- Add detailed documentation comparing tasks vs workflows
- Includes status tracking and error handling
- Bump version to 0.3.0 (new feature)

src/index.ts

@@ -15,6 +15,10 @@ export { default as Emails } from './collections/Emails.js'
 export { mailingJobs, sendEmailJob } from './jobs/index.js'
 export type { SendEmailTaskInput } from './jobs/sendEmailTask.js'
 
+// Workflows (includes the send email workflow)
+export { mailingWorkflows, sendEmailWorkflow } from './workflows/index.js'
+export type { SendEmailWorkflowInput } from './workflows/sendEmailWorkflow.js'
+
 // Main email sending function
 export { sendEmail, type SendEmailOptions } from './sendEmail.js'
 export { default as sendEmailDefault } from './sendEmail.js'