Restructure stats into delta, mask, and aggregate layers

loss_test.go

@@ -131,11 +131,11 @@ func TestLossWindowRefusesUnsentSeq(t *testing.T) {
 	}
 }
 
-// A gap written off while quiet — a cable measure's own link blip — charges
+// A gap written off while masked — a cable measure's own link blip — charges
 // nothing, however the eviction timing falls: even the gap's tail still
 // inside the window when the measure ends is presumed delivered. Counting
 // resumes seamlessly and later real gaps are still caught.
-func TestLossWindowQuietSlidesWithoutCharging(t *testing.T) {
+func TestLossWindowMaskedSlidesWithoutCharging(t *testing.T) {
 	w := newWindow(4 * lossSlots)
 	for seq := uint64(0); seq < 100; seq++ {
 		w.observe(seq, false)
@@ -143,7 +143,7 @@ func TestLossWindowQuietSlidesWithoutCharging(t *testing.T) {
 	// The blip: a huge jump arriving during the measure.
 	w.observe(2*lossSlots, true)
 	if got := w.lost.Load(); got != 0 {
-		t.Errorf("lost = %d after a quiet write-off, want 0", got)
+		t.Errorf("lost = %d after a masked write-off, want 0", got)
 	}
 
 	// The measure ends immediately — the worst case, with the gap's tail