GET /dashboard/stats now returns unassigned: open (not Completed or
Canceled) work orders with no dispatcher in the selected period, within the
caller's server-derived account scope. It uses the same filters as the
Unassigned board search, so the Dashboard number equals the list it drills
into. A dispatcher-scoped Dashboard has no unassigned work and returns 0.
The added service test asserts DashboardStatsDTO, which already carried
ScheduledTomorrow, PendingUplifts and AvetaPending, so it does not guard
the regression that was actually shipped: the DashboardController Stats
anonymous response dropping those keys and leaving the tiles empty.
Add DashboardControllerTests.GetStats_SerialisesKpiCountsOnWireObject,
which drives the controller and asserts the three keys are present on the
serialised wire object, so re-dropping any of them fails a test.
Also reword the pending-uplifts comment in DashboardServiceTests: the
Pending-only-vs-ChangesRequested exclusion is the behaviour the code
ships today, an open product call, not a settled review decision.
