grammar: the last two model calls that were still free text

The replier and the meeting summariser were the two call sites without a
GBNF. Both are exactly the shape that makes a Thinking variant answer with
its reasoning as prose, and neither had anything downstream that could
remove it.

The replier already parses {"response","mood"}, so it now sends the phraser's
grammar for that contract, exported once as phraser.ResponseGrammar so the
two definitions cannot drift.

The summariser stays text-in/text-out. The JSON wrapper is attached and
unwrapped in the daemon's Completer, so internal/capture is unchanged and a
Completer without a grammar still works.

The simulator told routing from phrasing by "has a grammar", which stopped
being true here; it now looks for the intent enum.

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

cmd/mavend/capture_test.go

@@ -116,3 +116,29 @@ func TestStopReturnsTranscriptAndNotesItWithoutASummary(t *testing.T) {
 		t.Fatalf("the meeting left no note behind: %+v", notes)
 	}
 }
+
+// The summary path is JSON-wrapped by summaryGrammar, and internal/capture must
+// keep seeing plain prose. These cover the wrapper and every way it can be
+// absent or broken, because a meeting summary is written once and not retried.
+func TestUnwrapSummary(t *testing.T) {
+	cases := []struct {
+		name string
+		in   string
+		want string
+	}{
+		{"grammar output", `{"summary": "решили купить насос"}`, "решили купить насос"},
+		{"multiline field", `{"summary": "- насос\n- бюджет"}`, "- насос\n- бюджет"},
+		{"empty marker survives", `{"summary": "пусто"}`, "пусто"},
+		{"empty field says nothing", `{"summary": ""}`, ""},
+		{"thinking prefix", "<think>hm</think>\n{\"summary\": \"итог\"}", "итог"},
+		{"no grammar, plain prose", "решили купить насос", "решили купить насос"},
+		{"broken json falls back", `{"summary": "обрыв`, `{"summary": "обрыв`},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			if got := unwrapSummary(c.in); got != c.want {
+				t.Errorf("unwrapSummary(%q) = %q, want %q", c.in, got, c.want)
+			}
+		})
+	}
+}