fix(qt): stabilize Japanese font fallback

cx

crates/qbz-qt/build.rs

@@ -317,8 +317,8 @@ fn build_rhi_items() {
         let moc = qtbuild.moc(&header, qt_build_utils::MocArguments::default());
         cc.file(source).file(&moc.cpp);
     }
-    // Plain helper, no QObject/moc: registers one script-specific bundled
-    // font through QFontDatabase before Main.qml constructs any text.
+    // Plain helper, no QObject/moc: registers script-specific bundled font
+    // fallbacks through QFontDatabase before Main.qml constructs any text.
     println!("cargo:rerun-if-changed=cxx/font_fallback.cpp");
     cc.file("cxx/font_fallback.cpp");
     // Plain helper, no QObject/moc: enumerates the exact QVulkanInstance that