fix(client): work through the findings from the coverage pass

214 items came out of writing the tests. Real defects are corrected, dead code
is removed rather than covered, and the tests that pinned the old behaviour
move with them.

Also drops two agent coverage scratch files that slipped into the coverage PR
and adds the ignore rule that keeps them out.

client/tests/unit/mobile/trip/useMPlanTimeline.test.ts

@@ -434,7 +434,7 @@ describe('useMPlanTimeline', () => {
     expect(useTripStore.getState().reservations.map(r => r.day_positions)).toEqual([{ 2: 0.5 }, undefined])
   })
 
-  it('FE-MOB-PLTL-024: surfaces a failed reorder as an error toast', async () => {
+  it('FE-MOB-PLTL-024: surfaces a failed reorder as an error toast and refetches the day', async () => {
     const actions = buildTripActions()
     actions.reorderAssignments.mockRejectedValue(new Error('offline'))
     const planner = makePlanner({ tripActions: actions })
@@ -442,6 +442,9 @@ describe('useMPlanTimeline', () => {
     await act(async () => { result.current.moveRow(result.current.merged[0], 'down') })
     await waitFor(() => expect(planner.toast.error).toHaveBeenCalledWith('offline'))
     expect(planner.updateRouteForDay).not.toHaveBeenCalled()
+    // The optimistic positions are dropped by refetching, not undone one by one.
+    expect(actions.refreshDays).toHaveBeenCalledWith(1)
+    expect(actions.loadReservations).toHaveBeenCalledWith(1)
   })
 
   it('FE-MOB-PLTL-025: falls back to the generic message for a non-Error failure', async () => {