Heirloom Toolchest NG Files

What's Changed

• libcommon: Fix the strjoin() function.
• libcommon, basename, timeout: Throw afterchar() in the garbage.
• apply, seq: Several improvements at the code, use correct types for size (size_t, ssize_t) instead of unsigned/signed long int, make the code fully C99-compatible.
• watch: Use system(3) per default, with the previous exec(3) being moved to the "-x" option, also fix interval display at the information header.
• xargs: The new "-0" option now permits that a null character, '\0', may be used as a delimiter instead of a new line.
• seq: Fix the "unsafe buffer usage" warning per making *argv[] a const, also use pfmt(3) instead of printf(3) since it treats the non-literal format string correctly, avoiding a compiler safety warning, and fix type mismatching.
• apply: Fix the "99 Bottles of Beer" example at the manual page, allocate memory for the buildcmd() buffer more correctly and intelligently, refactor significant sections of the code, fixed another possible memory leak at buildcmd(), added a '-e' flag for exit on error, improved code legibility.
• seq: Fix the step assumption so that if the stop is larger than the start, it will decrease one.
• Restore heirloom.spec, so now it can be built and properly packaged in RPM-based distributions.
• apply: Fix possible memory leak.

Full Changelog: https://github.com/Projeto-Pindorama/heirloom-ng/compare/250220...260903