CI installs [dev] with FORCE_COLOR, so Rich colorizes Typer --help and
splits an option name like --key into ANSI-wrapped segments
(\x1b[1;36m-\x1b[0m\x1b[1;36m-key\x1b[0m). The 4 raw-substring help
asserts passed locally (no color) but failed on all 9 CI test jobs.
Add a module-level _strip_ansi() helper and route the sign/verify/merge/
attest-emit --help substring checks through it (mirrors the v0.71.1
test_serve --record-thumbs fix). Confirmed locally under FORCE_COLOR=1:
all 4 pass; ANSI-strip alone is sufficient (no flag line-wraps).
Test-only change on the unreleased v0.71.2 — no version bump.