feat(news): F0 — schema, config y métodos DB del monitor RSS (inerte)

news_seen table (CREATE TABLE IF NOT EXISTS, sin migración) + índices.
Config NEWS_* (NEWS_ENABLED=false por defecto) + propiedad news_chat_id
(fallback al 1er TELEGRAM_ALLOWED_USERS). Métodos ResearchDB: source_seeded,
record_news_item, mark_news_notified, get_recent_news. Todo inerte: nada
lo invoca aún. feedparser ya estaba en requirements (6.0.12 >= 6.0).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/config.py

@@ -57,6 +57,20 @@ class Settings(BaseSettings):
     #            the write path. A `/generate blog en dry` arg forces dryrun per-call.
     seo_autofill: str = Field("off", env="SEO_AUTOFILL")
 
+    # News monitor (RSS de noticias UAP/OVNI) — inerte hasta NEWS_ENABLED=true.
+    NEWS_ENABLED: bool = Field(False, env="NEWS_ENABLED")
+    NEWS_POLL_INTERVAL_HOURS: int = Field(6, env="NEWS_POLL_INTERVAL_HOURS")
+    # Chat al que el monitor empuja novedades; si None -> 1er TELEGRAM_ALLOWED_USERS
+    # (ver propiedad news_chat_id).
+    NEWS_CHAT_ID: Optional[int] = Field(None, env="NEWS_CHAT_ID")
+    NEWS_KEYWORDS: str = Field(
+        "ovni,ovnis,uap,ufo,desclasificado,desclasificacion,declassified,"
+        "avistamiento,sighting,extraterrestre,non-human,nhi,grusch,pentagono,"
+        "pentagon,aaro,pursue,fenomeno aereo,whistleblower",
+        env="NEWS_KEYWORDS",
+    )
+    NEWS_MAX_ITEMS: int = Field(15, env="NEWS_MAX_ITEMS")
+
     # Alerts
     cost_alert_threshold: float = Field(0.15, env="COST_ALERT_THRESHOLD")
 
@@ -70,6 +84,15 @@ class Settings(BaseSettings):
             return []
         return [int(uid.strip()) for uid in self.telegram_allowed_users.split(",") if uid.strip()]
 
+    @property
+    def news_chat_id(self) -> Optional[int]:
+        """Chat destino del monitor de noticias: NEWS_CHAT_ID explícito o, si no
+        está definido, el primer TELEGRAM_ALLOWED_USERS."""
+        if self.NEWS_CHAT_ID is not None:
+            return self.NEWS_CHAT_ID
+        ids = self.allowed_user_ids
+        return ids[0] if ids else None
+
     @property
     def seo_autofill_enabled(self) -> bool:
         """True when autofill should run (either live 'on' or 'dryrun')."""