Allow bulk editing to change estimation unit on initiatives

If you change the capacity planning unit in your workspace from time to points (or vice versa), all records created going forward will use the new unit while previously created records will use the old unit.

With epics, features, and requirements, it is possible to convert existing records to using the new unit type via adjusting the capacity settings of the release they are in.

With initiatives, it is currently not possible to convert existing records to use the new unit type - they persist in using the original unit even when values are entered manually or rolled up from the correct units on the child record. Initiatives must be cloned or re-created to adopt the new unit.

There should be a way to adjust existing initiative units via bulk edit or a similar pathway when the default capacity unit is adjusted for a workspace, with the understanding that any existing estimates would be deleted as part of this process.