teardownFaultsFired

How many times close has selected a non-TeardownFault.None arm — counted at selection, before the arm runs.

At selection, not at completion, so a caller that bounds close in a withTimeout and never lets TeardownFault.Slow finish still leaves evidence the rig fired. A test asserting on teardown behaviour reads this as its precondition: a suite whose fault never reached the seam under test would otherwise pass by absence, which is the vacuity this knob exists to remove rather than relocate.