Move Resos API key to central Settings service; add sidebar scrollbar styling

Removes the standalone resos_api_key from the forecasting app's own
system_config table. All credential fetches now go through
central_settings.get_resos_credentials() / get_resos_credentials_sync()
which pull from the Settings app (LXC 116) via the internal integration
endpoint — the same pattern already used for NewBook. The Resos API
Config section is removed from the forecasting Settings page; users
manage the key in the central Settings app instead.

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

backend/jobs/resos_bookings_sync.py

@@ -5,7 +5,6 @@ Pattern: Replicates newbook bookings sync but adapted for Resos covers/stats
 """
 import json
 import logging
-import base64
 from datetime import date, datetime, timedelta
 from typing import Optional, Tuple, List, Dict, Any
 
@@ -20,27 +19,6 @@ logger = logging.getLogger(__name__)
 VALID_STATUSES = ('approved', 'arrived', 'seated', 'left')
 
 
-def get_config_value(db, key: str) -> Optional[str]:
-    """Get a configuration value from system_config table."""
-    result = db.execute(
-        text("SELECT config_value, is_encrypted FROM system_config WHERE config_key = :key"),
-        {"key": key}
-    )
-    row = result.fetchone()
-    if not row or not row.config_value:
-        return None
-
-    # Decrypt if encrypted
-    if row.is_encrypted:
-        try:
-            return base64.b64decode(row.config_value.encode()).decode()
-        except Exception as e:
-            logger.warning(f"Failed to decrypt {key}: {e}")
-            return row.config_value
-
-    return row.config_value
-
-
 def load_resos_custom_field_mappings(db) -> Dict[str, Dict[str, Any]]:
     """
     Load custom field mappings from resos_custom_field_mapping table.
@@ -194,11 +172,13 @@ async def sync_resos_bookings_data(
         )
         db.commit()
 
-        # Load Resos API key
-        api_key = get_config_value(db, 'resos_api_key')
+        # Load Resos API key from central Settings service
+        from services.central_settings import get_resos_credentials_sync
+        _resos_creds = get_resos_credentials_sync()
+        api_key = _resos_creds["api_key"] if _resos_creds else None
 
         if not api_key:
-            raise Exception("Resos API key not configured")
+            raise Exception("Resos API key not configured in central Settings")
 
         # Load mappings
         cf_mappings = load_resos_custom_field_mappings(db)