Fix advertising SMS shortcode to 5000990009.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/auth/sms.service.ts

@@ -21,7 +21,7 @@ export type SmsSendOptions = {
 };
 
 /** Default Meshkee advertising shortcode when a business has no own SMS number. */
-export const DEFAULT_ADVERTISING_SMS_SOURCE = '9000590009';
+export const DEFAULT_ADVERTISING_SMS_SOURCE = '5000990009';
 
 /** Gama batch size limit is undocumented; keep chunks conservative. */
 const GAMA_BULK_CHUNK_SIZE = 100;