test(gateway): isolate runtime PID identity fallback

[egilewski]

Summary

• isolate the unreadable-PID fallback test from the host process table
• stub the command-line probe explicitly when exercising the missing-inspection path
• add a separate regression case for rejecting an unrelated live process

Why

The fallback test previously supplied a live PID without controlling its
command line. A coincidental host process could therefore make the test depend
on external process state. This test-only change was discovered while
refocusing closed PR #70016 and is intentionally published separately from the
security implementation.

Validation

• tests/hermes_cli/test_gateway_runtime_health.py: 8 passed
• Ruff passes for the changed test file
• current-main merge-tree and diff checks pass

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Agent Disclosure

• Created by: GPT-5.6-sol with xhigh reasoning in Codex Desktop
• Human manually signed the commit

[teknium1]

Thanks for tightening this regression coverage. On current main, tests/hermes_cli/test_gateway_runtime_health.py:79 stubs _looks_like_gateway_process, but the exercised runtime-status path reads the live command line directly through gateway/status.py:557. The test can therefore depend on host PID 12345. The PR's explicit unreadable-command-line stub correctly reaches the persisted-record fallback at gateway/status.py:566; its new unrelated-process case exercises the rejection branch at gateway/status.py:557-565.

This is an automated hermes-sweeper review.

[egilewski]

Closing this PR because its documented purpose is a test-only isolation change discovered while refocusing closed issue #70016. The PR body does not identify an independent open issue or current product/security defect beyond that closed target, and #70016 is closed (GitHub provides no state reason). Recommendation: close rather than merge or redo as-is. The branch is left intact.