Root cause
arkts/builtin/static/ currently ships 61 ArkTS static builtin declaration files, but zh-cn/arkts/builtin/static/ mirrors only 7 of them (Array, ArrayBuffer, ArrayLike, Chrono, Comparable, Global, Set). The remaining 46 declaration files listed below have no Chinese counterpart, so Chinese readers of the ArkTS built-in API get no documentation for them at all.

Missing files (46):
BigInt, Boolean, BuiltinArray, BuiltinArrayAlgorithms, BuiltinArraySort, Byte, Char, Class, ConcatArray, Console, DataView, Date, Double, Error, Errors, Exceptions, Float, Function, Functions, Int, Intl, Iterator, Json, Jsonx, Long, Map, Math, Numeric, Object, ReadonlyArray, ReflecStaticField, Reflect, ReflectConstructor, ReflectInstanceField, ReflectInstanceMethod, ReflectProxy, ReflectStaticMethod, RegExp, Short, SparseArray, String, StringBuilder, Tuple, TypedArrays, TypedUArrays, retention

Steps to reproduce

cd interface_sdk-js
comm -23 \
  <(ls arkts/builtin/static/*.static.d.ets | xargs -n1 basename | sort) \
  <(ls zh-cn/arkts/builtin/static/*.static.d.ets | xargs -n1 basename | sort)

Demo code

# The zh-cn tree must stay a structural mirror of the English tree: every
# declaration line identical, only JSDoc prose translated. Today this check
# cannot even run for the 46 files, because the zh-cn file does not exist.
f=arkts/builtin/static/String.static.d.ets
diff <(grep -vE '^[[:space:]]*(\*|/\*|//)' "$f") \
     <(grep -vE '^[[:space:]]*(\*|/\*|//)' "zh-cn/$f")
# => diff: zh-cn/arkts/builtin/static/String.static.d.ets: No such file or directory

Observed and expected behavior
Observed: zh-cn/arkts/builtin/static/ contains 7 files; 46 of the 61 English declaration files have no Chinese documentation.
Expected: each of the 46 files has a zh-cn/ mirror whose declaration lines are byte-identical to the English source, whose line count matches, and whose JSDoc prose is Chinese while @syscap / @since / @stagemodelonly and other metadata tags stay untouched.