* Add shading to filler rows in the playout view
* Insert rows in Playout listing for gaps in the playout (station offline)
* Make FillerKind in PlayoutItemViewModel optional.
Remove Unscheduled enum in FillerKind.
* Correctly handle "Show Filler" also for Unscheduled fillers.
* Moved the Unscheduled item generation for the playout view to GetFuturePlayoutItemsByIdHandle to handle ShowFiller
* Includes for the PlayoutItemDetails moved to an extension for maintainability.
* Bugfix: Page size was more than the desired for pagination because of the inserted unscheduled items.
* Add specified colours for playout fillers to make them less intense.
* use common queryable
* add playout gap model and migrations
* insert playout gaps after playout build
* optimize get future playout items handler
* update changelog
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Co-authored-by: Jason Dove <1695733+jasongdove@users.noreply.github.com>