Support appended Safehouse profiles in runtime front doors

[clkao]

Append Safehouse policy files through Spacedock without bypassing the Claude, Codex, or Pi front doors.

What changed

• Add repeatable --safehouse-append-profile parsing and translation.
• Preserve literal paths, occurrence order, and host argument boundaries.
• Document the option and expose it in each host’s help.

Evidence

• 4/4 acceptance criteria verified independently; focused normal/race tests and real policy/CWD probes passed.
• Three adversarial mutations were detected. Full normal/race suites failed only the existing installed-Codex resolver check; no race warning.

---

9c