Update Go module path from github.com/kovetskiy/mark to
github.com/kovetskiy/mark/v16 across all packages and imports,
following Go module versioning conventions for major versions >= 2.
Also update README installation instructions and version string.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
ancestry grows to len(meta.Parents)+1. The subsequent warning log
indexed meta.Parents[len(ancestry)-1], which is one past the end of
meta.Parents, causing an out-of-bounds panic. Use ancestry[len(ancestry)-1]
to always reference the last element of the actual slice being validated.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
