Make mailer transport config optional, use Payload config fallback

- Updated MailingService to check for Payload's email transporter when plugin transport is not configured
- Enhanced error message to indicate transport is required in either plugin or Payload config
- Bump version to 0.0.5

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@xtr-dev/payload-mailing",
-  "version": "0.0.4",
+  "version": "0.0.5",
   "description": "Template-based email system with scheduling and job processing for PayloadCMS",
   "type": "module",
   "main": "dist/index.js",

src/services/MailingService.ts

@@ -38,10 +38,13 @@ export class MailingService implements IMailingService {
       if ('sendMail' in this.config.transport) {
         this.transporter = this.config.transport
       } else {
-        this.transporter = nodemailer.createTransport(this.config.transport as MailingTransportConfig)
+        this.transporter = nodemailer.createTransporter(this.config.transport as MailingTransportConfig)
       }
+    } else if (this.payload.email) {
+      // Use Payload's configured mailer
+      this.transporter = this.payload.email
     } else {
-      throw new Error('Email transport configuration is required')
+      throw new Error('Email transport configuration is required either in plugin config or Payload config')
     }
   }