Добавление assertion в bashunit по TDD

testing

add-assertion is a Claude Code skill that adds a new assertion function to the bashunit project following strict TDD methodology. The workflow spans five stages: planning (creating a task file at `.tasks/YYYY-MM-DD-add-assertion-name.md`), studying existing patterns in `src/assertions.sh` and `tests/unit/assert_test.sh`, TDD cycles of RED→GREEN→REFACTOR, integration (sourcing via `src/bashunit.sh`, exporting the function, running `./bashunit tests/`, and quality gates `make sa && make lint`), and documentation with a CHANGELOG.md update. Each assertion is covered by a basic success case, a failure case using `bashunit::console_results::print_failed_test` to capture output, and edge cases such as empty input, special characters, and nested structures. It is intended for bashunit contributors who need to extend the assertion library while staying consistent with the codebase's established conventions.