Improvements and fixes

Plant lists gain a "State" column, the sidebar's plant picker shows each plant's kind, and the "Turbines" page shows utilization and a reference curve.

• The monitor and dashboard plant lists now carry a "State" column — "Alert", "Warning", "Communication issue", "Disconnected", "Check" or "Inactive".
• The sidebar's plant picker now leads each plant with its kind and a battery marker, and typing a kind narrows the list.
• The "Turbines" page now shows each turbine's "Utilization (capacity factor)" and, where a datasheet is known, the maker's "Reference curve" with its "Validity band".
• A station row now marks an inverter with one open service item by that item's icon.