Enable/disable button "Delete Daily Plan" in the Daily Plan view

Current Situation

• A Daily Plan that contains submitted orders cannot be deleted as it is not possible to cancel and delete orders in a single transaction.
• When clicking the button for a day that contains submitted orders, nothing happens

Desired Behavior

• Delete Daily Plan for a single day:
  • The button "Delete Daily Plan" should be enabled only if all orders for the selected day are in the PLANNED state.
• Delete Daily Plan for a number of days:
  • The button "Delete Daily Plan" should be enabled if at least one of the selected days contains orders in the PLANNED state only. The Daily Plan will then be deleted for the days matching the criteria to hold PLANNED orders only.

Maintainer Note

• The functionality does not match the current handling of date ranges implemented with the GUI.
• As a prerequisite display of all orders selected in a date range has to be made available before enabling/disabling of the "Delete Daily Plan" button can be implemented. The larger change does not fit the scope of a minor issue in a maintenance release.