feat: delay show rotation during live recording window

Decouple the like-window boundary (Wed 10pm ET) from when the system
rotates to a new show. NTR_SHOW_ROTATION_DELAY_HOURS=2 keeps the
previous week's show visible during the ~2 hour recording, then creates
the new show at midnight.

Made-with: Cursor

src/ntr_fetcher/main.py

@@ -72,6 +72,7 @@ def run() -> None:
         show_day=settings.show_day,
         show_hour=settings.show_hour,
         poll_interval=settings.poll_interval_seconds,
+        rotation_delay_hours=settings.show_rotation_delay_hours,
     )
 
     app = create_app(
@@ -80,6 +81,7 @@ def run() -> None:
         admin_token=settings.admin_token,
         show_day=settings.show_day,
         show_hour=settings.show_hour,
+        rotation_delay_hours=settings.show_rotation_delay_hours,
         web_user=settings.web_user,
         web_password=settings.web_password,
         secret_key=settings.secret_key,