fix: additional bug fixes — CharSequence crash, local ref leaks, race conditions

Template fixes (regenerated all packages):
- Fix CharSequence return values unsafely cast to jstring — now returns
  *jni.Object instead of string to prevent JNI crash on non-String
  CharSequence implementations (SpannableString, StringBuilder, etc.)
- Fix local ref leak on GlobalRef promotion — save and delete original
  local ref after NewGlobalRef
- Fix local ref leak for string parameters — add deferred DeleteLocalRef
- Remove initSkipped dead code from all init.go files

Spec fixes:
- Fix NetworkCapabilities unexported type name (workCapabilities →
  NetworkCapabilities)

Hand-written code fixes:
- alarm/extract.go: add ShowIntent field, fix local ref leak
- location/extract.go: add Altitude/Bearing/Speed/Accuracy/Time fields,
  fix local ref leaks
- speech/new_tts.go: fix local ref leaks
- bluetooth/new_adapter.go: fix BluetoothManager GlobalRef leak
- proxy.go: protect SetProxyClassLoader with mutex, fix doProxyInit
  GlobalRef leak on partial failure
- intent_extra.go: fix local ref leaks in Put*Extra, fix GetBoolExtra
  error swallowing
- notification_extra.go: fix local ref leaks in NewChannel/NewBuilder
- graphics_extra.go: cache ARGB8888/MonospaceTypeface with sync.Once,
  fix local ref leaks in NewCanvas/NewPaint

ui.go fixes:
- Fix renderText GlobalRef leaks (Canvas/Paint never freed, plus early
  return paths)
- Fix data race: run function goroutine now uses local buffer
- Fix ignored NewStringUTF errors in permission handling

Example fixes:
- Remove capi imports from all 53 examples (use new jni.ObjectFromPtr)
- Fix clipboard example for CharSequence API change

Author: xaionaro@dx.center