phraser, mavend: read the fallbacks from the file (V-501)

The accessors are functions now, so the call sites that compared against one
literal compare against the entry instead: IsUnknownFallback and
IsSourcesFallback in the daemon tests, the entry key in the phraser tests. A
reworded variant no longer breaks a Go test.

The eval scores every variant on the persona checks the nudges already pass.

cmd/mavend/actions.go

@@ -66,7 +66,7 @@ func (h *reactiveHandler) actionChat(ctx context.Context, dec router.Decision) s
 		log.Printf("voice: chat: %v", err)
 	}
 	if reply == "" {
-		return phraser.ChatFallback
+		return phraser.ChatFallback()
 	}
 	return reply
 }

cmd/mavend/actions_query.go

@@ -798,7 +798,7 @@ func (h *reactiveHandler) queryGeneral(ctx context.Context, t *queryTurn) (strin
 	reply, err := h.phraseWorld(ctx, t.dec.Utterance, nil)
 	if errors.Is(err, phraser.ErrNoWorldModel) {
 		log.Printf("voice: %q needs the world model and it is not available", t.dec.Utterance)
-		return worldGap, true
+		return worldGap(), true
 	}
 	if err != nil || reply == "" {
 		return "не знаю.", true

cmd/mavend/query_recall_test.go

@@ -121,8 +121,8 @@ func TestQueryRecallNoteCanWin(t *testing.T) {
 			{text: "выучил пару аккордов", score: 0.50, kind: "note"},
 		})
 		reply := askQuery(t, h, q)
-		if want := "вот что я нашла: молоко стоит в холодильнике"; reply != want {
-			t.Errorf("reply %q, want %q", reply, want)
+		if !phraser.IsSourcesFallback(reply, "молоко стоит в холодильнике") {
+			t.Errorf("reply %q, want the note read back", reply)
 		}
 		// One text, the winning memory's — the answer came from the memory
 		// pass, not from handing the phraser every note in the table.
@@ -151,7 +151,7 @@ func TestQueryRecallNoteCanWin(t *testing.T) {
 			{text: "молоко стоит в холодильнике", score: 0.860, kind: "note"},
 			{text: "молоко закончилось", score: 0.858, kind: "note"},
 		})
-		if reply := askQuery(t, h, q); reply != "не знаю." {
+		if reply := askQuery(t, h, q); !phraser.IsUnknownFallback(reply) {
 			t.Errorf("reply %q, want silence", reply)
 		}
 	})

cmd/mavend/worldmodel.go

@@ -23,7 +23,11 @@ type worldPhraser interface {
 // question about his meeting came back as a swimming competition in Nottingham.
 // Naming the gap is the rule CLAUDE.md already applies to a sibling service
 // being down.
-const worldGap = "сейчас не могу ответить — большая модель недоступна, а придумывать не хочу."
+//
+// The wording lives in fallbacks_ru_v1.json and is fixed there, not picked from
+// variants: this sentence names one specific gap and must not drift into a
+// general "I don't know".
+func worldGap() string { return phraser.WorldGap() }
 
 // phraseWorld asks the world model, or reports the gap.
 //

cmd/mavend/worldmodel_test.go

@@ -35,7 +35,7 @@ func TestQueryGeneralNamesTheGap(t *testing.T) {
 	if !ok {
 		t.Fatal("queryGeneral passed on the last source in the chain")
 	}
-	if reply != worldGap {
+	if reply != worldGap() {
 		t.Fatalf("reply = %q, want the named gap", reply)
 	}
 	if g.worldCalls != 1 {
@@ -51,7 +51,7 @@ func TestQueryGeneralWithoutAWorldModelIsUnchanged(t *testing.T) {
 	if !ok {
 		t.Fatal("queryGeneral passed on the last source in the chain")
 	}
-	if reply != "не знаю." {
+	if !phraser.IsUnknownFallback(reply) {
 		t.Fatalf("reply = %q, want the Stub's answer", reply)
 	}
 }
@@ -61,12 +61,12 @@ func TestQueryGeneralWithoutAWorldModelIsUnchanged(t *testing.T) {
 // English in it.
 func TestWorldGapIsInPersona(t *testing.T) {
 	for _, bad := range []string{"вы", "ваш", "рад ", "дорогой", "милый"} {
-		if strings.Contains(worldGap, bad) {
-			t.Errorf("the gap phrase contains %q: %s", bad, worldGap)
+		if strings.Contains(worldGap(), bad) {
+			t.Errorf("the gap phrase contains %q: %s", bad, worldGap())
 		}
 	}
-	if strings.ContainsAny(worldGap, "abcdefghijklmnopqrstuvwxyz") {
-		t.Errorf("the gap phrase has Latin letters in it: %s", worldGap)
+	if strings.ContainsAny(worldGap(), "abcdefghijklmnopqrstuvwxyz") {
+		t.Errorf("the gap phrase has Latin letters in it: %s", worldGap())
 	}
 }