Red-team follow-up to #1341: the original fix only guarded --print but
Claude accepts -p as the short form, and CCS itself passes -p in
headless-executor.ts. Without this check the security bypass survived
via the short flag.
Added regression tests: ['-p', 'agents'], ['-p', 'doctor'], ['-p']
alone, and injector short-circuit verification for -p form.