feat: home growth auto(7→1) and hourly recent-video snapshot

- Add analytics.home_growth_days (auto|1|7); API growth_days=auto tries 7 then 1
- Homepage shows active window and growth-board link; clearer empty reason
- New snapshot_recent scheduler task (schedule.recent_snapshot_minutes/days)
- run_recent_videos refreshes new aids only; never touches completed/backup
- Full 00:01 job keeps ok=1 skip (covers hourly refresh within 1h); mutex with recent

reaction_board/repository.py

@@ -637,6 +637,19 @@ class Repository:
             return [int(row["aid"]) for row in rows]
         return self.db.read(run)
 
+    def video_aids_recent_for_snapshot(self, *, since_pubdate: int) -> list[int]:
+        """近 N 天新视频：按 pubdate 墙钟窗口（since_pubdate = now - days*86400）。"""
+        def run(conn: sqlite3.Connection) -> list[int]:
+            rows = conn.execute(
+                "SELECT aid FROM video "
+                "WHERE status IN ('active', 'unfaved') "
+                "AND pubdate IS NOT NULL AND pubdate >= ? "
+                "ORDER BY aid",
+                (int(since_pubdate),),
+            ).fetchall()
+            return [int(row["aid"]) for row in rows]
+        return self.db.read(run)
+
     def pending_snapshot_aids(self, stat_date: str) -> list[int]:
         """当天仍缺成功快照的追踪视频；用于新入库/恢复后的同日补采。"""
         def run(conn: sqlite3.Connection) -> list[int]: