test(smoke): smoke tests do not cover FTPS (implicit or explicit)

gh issue create --title "test(smoke): smoke tests do not cover FTPS (implicit or explicit)" --label "test,audit,priority:low" --body "## Finding

tests/smoke.sh runs the action against a plain FTP server only. FTPS scenarios (03 and 04 in the integration suite) are not exercised by the smoke gate. A FTPS-only regression could pass smoke and break in production.

## Affected code

- tests/smoke.sh
- (maybe a new tests/smoke-ftps.sh)

## Reproduction

1. Inspect tests/smoke.sh: no FTPS test case.

## Suggested fix

Add a smoke test that runs the action with INPUT_FTP_SSL=true and a self-signed cert. Or add a separate tests/smoke-ftps.sh target and wire it into the Makefile.

## Source

F2 audit 2026-09-03 (tests audit). Reporter: subagent-pekodbj7.

## Related

- Part of EPIC #[epic-number]
- Closes: #NONE (no existing issue)
- Related: #120 (FTPS integration coverage — closed, superseded by current scenarios)"

Start by reading tests/smoke.sh and compare its plain FTP coverage with FTPS scenarios 03 and 04 in the integration suite. Check the Makefile to see how smoke targets are wired, then determine whether the FTPS case belongs in tests/smoke.sh or a separate tests/smoke-ftps.sh. Done means the smoke gate runs an FTPS test with INPUT_FTP_SSL=true and a self-signed certificate.

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