Added the Hard Discard feature for the discard rule: If checked and the slice is discarded, the slice will be directly deleted without any archiving. Use this feature to reduce temporary storage needed.

If a slice is set to Discarded, the active rule will not be nullified anymore, but will contain the rule that led to the slice becoming discarded. This will help in analyzing slices.

Improved error handling and robustness of the Execute Count Query feature.