feat(researchowl): activar monitor de noticias RSS (NEWS_ENABLED=true)

Flip del flag que deja operativo el monitor F0-F2 ya desplegado en
b1c5bc73. Defaults: poll cada 6h, digest al primer TELEGRAM_ALLOWED_USERS.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

researchowl/deployment.yaml

@@ -92,6 +92,8 @@ spec:
                   key: ghost-api-key-en
             - name: SEO_AUTOFILL
               value: "on"
+            - name: NEWS_ENABLED
+              value: "true"
           volumeMounts:
             - name: data
               mountPath: /data