Env-var-only seams (§3.2), zero logic change (diff is only the seam
lines): REPO gains PROFILE_REPO_OVERRIDE (cd -P already correct, no
bugfix needed here — only toggle-external.sh had the logical-cd bug);
CLAUDE_BIN="${CLAUDE_BIN:-claude}" replaces the 8 bare `claude`
invocation sites (4 `command -v claude` checks + `claude plugin list`/
`plugin enable`/`plugin disable`/`mcp list`). The advisory `info "..."`
hint strings that tell a HUMAN what to type stay literal "claude" —
those aren't invocations.
Unlocks (BACKLOG, not built in this job): a hermetic profile.sh suite
via HOME/REPO/CLAUDE_BIN injection, promoting J4-19 from UNTESTABLE.
Verified: bash -n clean, shellcheck clean, `profile.sh current`/`list`
behaviorally unchanged against the real repo, full `make test` exit 0.
Bastien Chanot
04da103ed6