R1 (P1): a quoted export still ran code when the key was a bash special
variable (RANDOM=a[$(cmd)] is evaluated arithmetically on assignment).
envfile.RESERVED (bash's own variables, plus BASH_/COMP_/READLINE_
prefixes) is skipped with a line-numbered warning by both loaders; a test
keeps it covering every variable a clean bash defines. The wrapper also
hands SCRIPT_DIR/REPO_ROOT/TARGET_ENV to the parser as environment, so the
file cannot replace the variables it has already set.
R2 (P2): SKS_QUIESCENT_TRIES reached `for ((i < tries))` through a function
argument; it is normalised at the call site (minimum 0). B5 now requires
every integer-looking env default in the shell code to be normalised or
listed in NOT_ARITHMETIC with where it goes, and exercises _pane_quiescent.
R3 (P2): _positive_int strips leading zeros and rejects more than nine
significant digits before int(), like mam_int; 5000-digit inputs no longer
raise in the runner.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>