Add configurable 30-day NewBook rate rescrape on 2/4/6/12h intervals

Intraday rescrape jobs are distributed evenly between the main nightly run
(05:20) and cover only the next 30 days — lightweight complement to the
full 720-day nightly sweep. Interval is configurable from the Newbook tab
in Settings and takes effect immediately without a container restart.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/api/bookability.py

@@ -781,6 +781,90 @@ async def get_occupancy_history(
     }
 
 
+# ============================================
+# RESCRAPE INTERVAL CONFIG
+# ============================================
+
+def _rescrape_times_from_config(interval_hours: int, time_str: str) -> list:
+    """Compute extra rescrape fire times (HH:MM strings) from interval and base time."""
+    try:
+        parts = time_str.split(':')
+        base_hour, base_minute = int(parts[0]), int(parts[1])
+    except (ValueError, IndexError):
+        base_hour, base_minute = 5, 20
+    if interval_hours not in (2, 4, 6, 12):
+        return []
+    return [
+        f"{(base_hour + offset) % 24:02d}:{base_minute:02d}"
+        for offset in range(interval_hours, 24, interval_hours)
+    ]
+
+
+@router.get("/config/rescrape-schedule")
+async def get_rescrape_schedule(
+    db: AsyncSession = Depends(get_db),
+    current_user: dict = Depends(get_current_user)
+):
+    """Return current 30-day rescrape interval config and computed fire times."""
+    result = await db.execute(
+        text("""
+            SELECT config_key, config_value FROM system_config
+            WHERE config_key IN ('newbook_rescrape_interval_hours', 'sync_newbook_current_rates_time')
+        """)
+    )
+    cfg = {row.config_key: row.config_value for row in result.fetchall()}
+    try:
+        interval_hours = int(cfg.get('newbook_rescrape_interval_hours') or '0')
+    except ValueError:
+        interval_hours = 0
+    time_str = cfg.get('sync_newbook_current_rates_time') or '05:20'
+    return {
+        "interval_hours": interval_hours,
+        "base_time": time_str,
+        "rescrape_times": _rescrape_times_from_config(interval_hours, time_str),
+    }
+
+
+class RescrapeIntervalBody(BaseModel):
+    interval_hours: int
+
+
+@router.post("/config/rescrape-interval")
+async def set_rescrape_interval(
+    body: RescrapeIntervalBody,
+    db: AsyncSession = Depends(get_db),
+    current_user: dict = Depends(get_current_user)
+):
+    """Save 30-day rescrape interval and live-reload the scheduler jobs."""
+    if body.interval_hours not in (0, 2, 4, 6, 12):
+        raise HTTPException(status_code=400, detail="interval_hours must be 0, 2, 4, 6, or 12")
+
+    await db.execute(
+        text("""
+            INSERT INTO system_config (config_key, config_value)
+            VALUES ('newbook_rescrape_interval_hours', :val)
+            ON CONFLICT (config_key) DO UPDATE SET config_value = EXCLUDED.config_value
+        """),
+        {"val": str(body.interval_hours)}
+    )
+    await db.commit()
+
+    from scheduler import apply_newbook_rescrape_schedule
+    apply_newbook_rescrape_schedule()
+
+    time_result = await db.execute(
+        text("SELECT config_value FROM system_config WHERE config_key = 'sync_newbook_current_rates_time'")
+    )
+    time_row = time_result.fetchone()
+    time_str = (time_row.config_value if time_row and time_row.config_value else None) or '05:20'
+    return {
+        "status": "saved",
+        "interval_hours": body.interval_hours,
+        "base_time": time_str,
+        "rescrape_times": _rescrape_times_from_config(body.interval_hours, time_str),
+    }
+
+
 @router.post("/refresh-date/{rate_date}")
 async def refresh_single_date(
     rate_date: str,