mainGrid(), unionOfActiveCells(), computeUnionOfActiveCells(), and statisticsCaseCollection() default to null/no-op. Remove redundant overrides from RimEclipseCaseEnsemble.
Introduce RimReservoirGridEnsemble and RimReservoirGridEnsembleBase to manage ensembles of grid-only Eclipse cases. Enable detection of identical grids for shared operations and statistics. Integrate grid ensembles into project structure, UI, and menu system. Refactor statistics and view handling to support both case groups and grid ensembles via a common interface. Add deferred grid loading, robust case referencing, and migration for well data source fields. New features and menu items allow creation and management of grid ensembles from file sets, enabling new workflows for grid-only ensemble analysis.
* Remove unused includes
* Use designated initializers struct members
* Add warning for active cell opm grid reader
* Moves radial grid import to file readers
* Adapts cell range filter labels for radial grids