fix: an asleep browser Lane is not a stalled one on the admin page (#110)

Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>

backend/internal/latest/poller_test.go

@@ -1388,6 +1388,11 @@ func TestBrowserLaneWakeThresholds(t *testing.T) {
 	if got := browser.callCount(); got != 0 {
 		t.Fatalf("browser fetches with 3 freshly-due series = %d, want 0 (Chrome stays asleep)", got)
 	}
+	// The owner's page reads this state off the snapshot, and Due-without-
+	// Checked has to be distinguishable there from a Lane that has stopped.
+	if lane := laneByName(t, p, "kagane"); !lane.Asleep || lane.Due != 3 || lane.Checked != 0 {
+		t.Fatalf("asleep kagane lane = %+v, want Asleep with 3 due and 0 checked", lane)
+	}
 	// 5 due crosses the count threshold.
 	for i := 3; i < 5; i++ {
 		seed(i)
@@ -1396,6 +1401,9 @@ func TestBrowserLaneWakeThresholds(t *testing.T) {
 	if got := browser.callCount(); got != 5 {
 		t.Fatalf("browser fetches with 5 due series = %d, want 5", got)
 	}
+	if lane := laneByName(t, p, "kagane"); lane.Asleep {
+		t.Fatalf("woken kagane lane still reports Asleep: %+v", lane)
+	}
 	// A single long-neglected series wakes the browser by age alone.
 	seedForCheck(t, s, "kagane:ancient", "https://kagane.to/series/ancient", 0)
 	p.runOnce(context.Background())
@@ -1404,6 +1412,19 @@ func TestBrowserLaneWakeThresholds(t *testing.T) {
 	}
 }
 
+// laneByName pulls one Lane out of the poller's snapshot, failing rather than
+// returning a zero LaneState a caller would assert against by accident.
+func laneByName(t *testing.T, p *Poller, site string) LaneState {
+	t.Helper()
+	for _, lane := range p.LaneStatus().Lanes {
+		if lane.Site == site {
+			return lane
+		}
+	}
+	t.Fatalf("no %q lane in the snapshot", site)
+	return LaneState{}
+}
+
 // When one browser Lane loses the sidecar, the round's remaining browser
 // Lanes are skipped: every fetch would fail anyway, and their Series must not
 // burn their stamps on a dead Chrome (issue #100).