fix: disable Authorization header for Strapi public API access

- Modify getHeaders() to always return empty object
- Prevents sending invalid Bearer token that causes 401 errors
- Strapi Public role permissions configured for unauthenticated access
- Will allow proper article sync from Strapi to backend

backend/src/modules/strapi.service.ts

@@ -106,12 +106,8 @@ export class StrapiService {
   }
 
   private getHeaders() {
-    // Only include Authorization header if token is set
-    if (this.strapiApiToken) {
-      return {
-        Authorization: `Bearer ${this.strapiApiToken}`,
-      };
-    }
+    // Use public API access - no authentication needed
+    // Strapi Public role has been configured to allow article access
     return {};
   }