feat: CJK font rendering, force quit confirmation, settings i18n

- Rebuild CJK font subset (1421 glyphs) and convert CFF→TTF for
  stb_truetype compatibility, fixing Chinese/Japanese/Korean rendering
- Add force quit confirmation dialog with cancel/confirm actions
- Show force quit tooltip immediately on hover (no delay)
- Translate hardcoded English strings in settings dropdowns
  (auto-lock timeouts, slider "Off" labels)
- Fix mojibake en-dashes in 7 translation JSON files
- Add helper scripts: build_cjk_subset, convert_cjk_to_ttf,
  check_font_coverage, fix_mojibake

src/embedded/embedded_fonts.cpp.in

@@ -12,4 +12,4 @@ INCBIN(ubuntu_regular,  "@CMAKE_SOURCE_DIR@/res/fonts/Ubuntu-R.ttf");
 INCBIN(ubuntu_light,    "@CMAKE_SOURCE_DIR@/res/fonts/Ubuntu-Light.ttf");
 INCBIN(ubuntu_medium,   "@CMAKE_SOURCE_DIR@/res/fonts/Ubuntu-Medium.ttf");
 INCBIN(material_icons,  "@CMAKE_SOURCE_DIR@/res/fonts/MaterialIcons-Regular.ttf");
-INCBIN(noto_cjk_subset, "@CMAKE_SOURCE_DIR@/res/fonts/NotoSansCJK-Subset.otf");
+INCBIN(noto_cjk_subset, "@CMAKE_SOURCE_DIR@/res/fonts/NotoSansCJK-Subset.ttf");