The bitwise operator tests used decimal literals exceeding u32 range, causing undefined behavior when converting double to u32 on some compilers. This replaces those values with hex equivalents that fit within u32, removes tests for values past max u32, and adds TODO comments for future handling. Also simplifies the `num_bitwiseNot` primitive by removing the intermediate `wideVal` variable, and fixes minor formatting in `util/test.py`.
- Delete wren_io.c, wren_io.h, and io.wren source files
- Remove multi-arity print overloads and IO.read/IO.time methods
- Add System class with print, printAll, write, writeAll methods to core.wren
- Update all documentation examples and README to use System.print instead of IO.print
The benchmark directory is relocated from the project root into the test directory, and all scripts, documentation links, and gitignore paths are updated accordingly. The test runner is also refactored to explicitly walk subdirectories (core, io, language, limit) instead of using a single test root, and a new test/README.md is added to document the test suite structure. Additionally, the constructor test for the Foo class is updated to add a zero-arity constructor and adjust expected output strings.
