Harden managed profile process cleanup

[euforic]

Summary

• close profile-owned helper processes even after the main managed instance exits or is reparented
• clean verified orphan helpers before relaunching the same profile
• preserve signature, canonical path-containment, stable process-identity, and cross-profile isolation checks
• document the managed helper lifecycle and opt-in installed-profile validation

Root cause

Profile process discovery recognized app-bundle processes carrying the configured user-data argument, but a profile-local Computer Use helper can execute from the profile state directory without that argument. Once detached from the main process tree, that helper could remain running after the profile was closed.

Validation

• swift test — 176 tests passed, 6 opt-in tests skipped
• focused launcher suite — 36 tests passed, 3 opt-in tests skipped
• active managed-profile teardown — selected main/helper processes exited while the stock instance and unrelated helpers were unchanged
• real process-identity rejection coverage
• installed signature and temporary lifecycle validation
• ./script/build_app.sh
• ./script/package_app.sh
• strict application signature verification
• disk-image integrity verification
• final packaged application launch

Privacy and Security

• No credentials, account data, private transcripts, local paths, or unredacted logs are included.
• Profile ownership, canonical containment, signature, and stable process-identity checks remain fail closed.

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Capture helpers that appear after the final snapshot

When a verified profile helper starts or respawns after this second snapshot—for example, while the main application is terminating—it is never added to capturedProcesses, so it receives neither this SIGTERM nor the later SIGKILL. remainingProcesses nevertheless rediscovers the helper on every poll, meaning a helper that remains alive forces closeTimedOut; when cleanup was initiated by open, this also prevents the replacement instance from launching. Refresh and signal newly verified stable identities during the wait or kill phase rather than freezing the captured set here.

AGENTS.md reference: AGENTS.md:L19-L20

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