Add optional slug field to business registration form

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

src/api/types.ts

@@ -50,6 +50,7 @@ export type BusinessRegistrationRequest = {
 export type CreateBusinessRegistrationPayload = {
   title: string;
   categoryId: string;
+  slug?: string;
   description?: string;
   contactPhone?: string;
   address?: string;