Tell him when an expired clarify question is dropped

Vikunja #382. A parked clarifying question past its TTL was discarded
silently on read; now she says the old request is gone and the newly
spoken words are still routed as a fresh utterance.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CGeSZxh1DCtRxmFVSYVGvJ

internal/dialogue/clarify_test.go

@@ -60,6 +60,28 @@ func TestClarifyStoreGetPutDelete(t *testing.T) {
 	}
 }
 
+// TestClarifyStoreTakeExpired — TakeExpired reports (and drops) only a question
+// whose TTL ran out.
+func TestClarifyStoreTakeExpired(t *testing.T) {
+	s := NewClarifyStore(time.Minute)
+	if s.TakeExpired("voice", base) {
+		t.Fatal("nothing parked ⇒ nothing expired")
+	}
+	s.Put("voice", &PendingQuestion{Missing: []Slot{SlotTime}, Asked: base, TTL: time.Minute})
+	if s.TakeExpired("voice", base.Add(30*time.Second)) {
+		t.Fatal("a live question must not report as expired")
+	}
+	if s.Get("voice", base.Add(30*time.Second)) == nil {
+		t.Fatal("a live question must survive TakeExpired")
+	}
+	if !s.TakeExpired("voice", base.Add(2*time.Minute)) {
+		t.Fatal("a stale question must report as expired")
+	}
+	if s.TakeExpired("voice", base.Add(2*time.Minute)) {
+		t.Fatal("TakeExpired must drop the question, so the second call is false")
+	}
+}
+
 func TestNewClarifyStoreDefaultTTL(t *testing.T) {
 	s := NewClarifyStore(0)
 	q := &PendingQuestion{Asked: base}