feat: Add IsFixed parameter to DataGrid #3920
Description
Add a boolean parameter IsFixed to the FluentDataGrid component (like the IsFixed parameter that exists on the standard Blazor Cascading Value component).
The default value of false means the grid continues to behave like it did in v4.11.9. When set to true, the developer can indicate that the grid's dataset is not expected to change during its lifetime.
This replaces the new refresh logic that was implemented in v4.12.0