condition bug fix

adapt to Zig 0.16.0 and change major version to 4.0.0

update to version 3.1.1

refactor: eliminate zero-cost fields for mutex and writer when unused

updated to version 3.0.0

update to version 2.1.0

refactor and rework with atomic support, reducing overhead

release 1.3.0

updated to new patch 1.2.1

added documentation for thread safe mode