fix(gateway): block uninstall from gateway child

[KeaneYan]

Summary

• re-scope the fix to the remaining gateway-child gap on current main: gateway uninstall
• reject hermes gateway uninstall when _HERMES_GATEWAY=1
• extend the shared lifecycle guard to catch hermes gateway uninstall and direct launchctl bootout ... hermes.gateway commands
• retain the existing command-level stop/restart protections instead of duplicating them in launchd_stop()

Tests

• scripts/run_tests.sh tests/hermes_cli/test_gateway_restart_loop.py -q (70 passed)
• ruff check hermes_cli/gateway.py cron/lifecycle_guard.py tests/hermes_cli/test_gateway_restart_loop.py

Rebased onto current main (e589b73).

[teknium1]

Thanks for identifying the launchd child-process hazard. The restart and stop portions have since been covered on current main: hermes_cli/gateway.py:6778 and :6871 reject gateway-child stop/restart, while tools/terminal_tool.py:2257 blocks matching lifecycle commands before execution.

Problems

• The launchd_stop() guard and its dispatch tests duplicate those current command-level protections, so they need rework rather than a direct cherry-pick.
• A narrower gap remains: hermes_cli/gateway.py:6681 dispatches uninstall to launchd_uninstall(), whose launchctl bootout at :4165 is not guarded. The current terminal lifecycle pattern in cron/lifecycle_guard.py:54 covers only restart|stop.

Suggested changes

• Re-scope the salvage to protect gateway uninstall from a gateway child, using the existing marker guard or the proposed ancestry check, and add a regression for that current path.
• Update stop/restart tests to assert the existing command-level behavior.

Automated hermes-sweeper review.

[teknium1]

Merged via PR #93336 (c94ee2e) — your uninstall guard was cherry-picked with your authorship preserved in git log, adapted to the PID-ownership gate that replaced the raw env check (#92560), so CLI sessions spawned under the gateway tree can still uninstall while the gateway itself cannot self-target. The launchctl bootout coverage from your original scope had already landed via #93297. Thanks for the long patience on this one — filed in May, landed in August, but landed.