Replace the global `io` singleton object with a static `IO` class, moving the `write` native from the instance to the metaclass. Update all benchmark, example, and test files to use `IO.write()` instead of `io.write()`.
Extract inline list growth logic into `ensureListCapacity` helper and add `validateIndex` function supporting negative indices. Implement `list_clear` primitive that resets count to zero without freeing memory, and `list_insert` primitive that shifts elements right and inserts at validated position. Add comprehensive test suites for both operations covering empty lists, normal/negative indices, and return values.
