* DashList: Stop using IDs
* DashLinks: Stop using IDs
* BackendSrv: Do not use ID for search endpoint
* DashboardDataDTO: Remove ID
* Remove unused properties from DashboardSearchItem
* Add NumberInput to core slider
* Change opacity interpretation
To be consistent with other layers, and CSS, opacity of 0 is fully
transparent and an opacity of 1 is fully opaque.
* Add state management for slider.
* Ensure number input step matches slider
* Style input width based on expected digits
* Improve styling for number input validation error
