`normalize_command` now strips heredoc bodies before shlex tokenization
so a user's `auto_allow = ["cat > file.txt"]` pattern matches the
heredoc form `cat <<EOF > file.txt\nbody\nEOF` cleanly. Recognises the
common forms (`<<DELIM`, `<<-DELIM`, `<<'DELIM'`, `<<"DELIM"`) while
leaving the here-string operator (`<<<`) untouched.
Six unit tests cover: simple body strip, dash form, quoted delimiter,
non-heredoc passthrough, here-string preservation, and the end-to-end
pattern-match path.
Hunter Bown
f6c7a36076