mavend: a clarify asks differently the second time (V-457)

Every clarify turn said one sentence per gap, and a re-ask repeated it word
for word. A question he already failed to answer is the worst one to ask
again unchanged: the second wording is what tells him which part she missed.

clarifytemplates.go holds three wordings per slot, picked by attempt rather
than at random — short first, then naming the gap, then spelling it out with
an example. Past the end she keeps the most explicit one instead of wrapping
back to the short question he has already not answered.

The intents with nothing identifiable to ask about (note, query, chat,
system) kept the stub's single "не совсем поняла — можешь переформулировать?",
which is the line he hears whenever she misses him completely. Four wordings
now, picked by a hash of the utterance so one question asked twice reads the
same and two different misses do not.

Still no model call on this path: the resident model would wander, and this
text has to be right every time. No schema_version either, unlike the nudge
templates — these are Go constants, so no file can drift out of step with the
code that reads it. The persona test already in clarify_test.go covers the
new lines.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

cmd/mavend/replier_llm.go

@@ -24,7 +24,12 @@ func newLLMReplier(c phraser.Completer, block func() string) *llmReplier {
 // answer from the stub, which is what keeps a turn from breaking on the model.
 func (r *llmReplier) Reply(d router.Decision) string {
 	if d.Clarify {
-		return r.stub.Reply(d)
+		// The deck, not the stub's single sentence: a clarify she cannot turn
+		// into a question is the line he hears most often when she misses him,
+		// and it used to be the same words every time (Vikunja #457). Still no
+		// model call — this text has to be right every time, and it is not worth
+		// a generation to say something this small.
+		return clarifyMissedLine(d)
 	}
 	out, err := r.p.PhraseReply(context.Background(), d)
 	if err != nil || out == "" {