fix: changed detected by scanner but no updated by render layer

internal/storage/sqlite_test.go

@@ -211,3 +211,28 @@ func TestSQLiteStorage_SearchByTag(t *testing.T) {
 		t.Fatalf("expected tag match to be n2")
 	}
 }
+
+func TestSQLiteStorage_Create_Upsert(t *testing.T) {
+	st := newSQLiteStorage(t)
+
+	ts := time.Date(2026, 2, 3, 12, 0, 0, 0, time.UTC)
+	n := sampleNote("n1", "notes/alpha.md", "Alpha", "one", ts)
+	if err := st.Create(n); err != nil {
+		t.Fatalf("create note: %v", err)
+	}
+
+	n.Content = "updated"
+	n.Title = "Alpha Updated"
+	n.UpdatedAt = ts.Add(2 * time.Hour)
+	if err := st.Create(n); err != nil {
+		t.Fatalf("upsert note: %v", err)
+	}
+
+	got, err := st.Get("n1")
+	if err != nil {
+		t.Fatalf("get note: %v", err)
+	}
+	if got.Title != "Alpha Updated" || got.Content != "updated" {
+		t.Fatalf("expected note to be updated, got %+v", got)
+	}
+}