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

CMakeLists.txt

@@ -419,6 +419,20 @@ configure_file(
     @ONLY
 )
 
+# INCBIN uses .incbin assembler directives that reference font files at
+# assembly time — CMake doesn't track these implicit dependencies.
+# Tell CMake that the generated source depends on the actual font binaries
+# so a font file change triggers recompilation.
+set_source_files_properties(
+    ${CMAKE_BINARY_DIR}/generated/embedded_fonts.cpp
+    PROPERTIES OBJECT_DEPENDS
+    "${CMAKE_SOURCE_DIR}/res/fonts/Ubuntu-R.ttf;\
+${CMAKE_SOURCE_DIR}/res/fonts/Ubuntu-Light.ttf;\
+${CMAKE_SOURCE_DIR}/res/fonts/Ubuntu-Medium.ttf;\
+${CMAKE_SOURCE_DIR}/res/fonts/MaterialIcons-Regular.ttf;\
+${CMAKE_SOURCE_DIR}/res/fonts/NotoSansCJK-Subset.ttf"
+)
+
 add_executable(ObsidianDragon
     ${APP_SOURCES}
     ${CMAKE_BINARY_DIR}/generated/embedded_fonts.cpp