refactor(plugin): port security policy resolution to TypeScript

[kmbroai]

Summary

Replace the Python SECURITY.md resolver and its tests with a typed helper bundled alongside the MCP runtime. Policy discovery and root-to-leaf guidance now run through the existing Node launcher.

Stacked on #798.

Changes

• Preserve policy containment, symlink and junction behavior, the existing byte limit, UTF-8 handling, home expansion, inventory ordering, argument behavior, and output formats.
• Use the native primitives for POSIX path bytes and Windows UTF-16 arguments, environment values, working directories, and filesystem paths. Compare canonical Windows path components without losing characters during Unicode case conversion.
• Update callers to launch_codex_security_mcp[.cmd] --helper resolve-security-md --repo PATH [--list | --scope PATH] [--out PATH]; output still defaults to stdout. There are no new top-level CLI flags.
• Remove the migrated Python implementation and tests. Add built-helper coverage and Windows runtime proofs on Node 20.0 and 22.13.

Testing

• Built policy and launcher tests: 34 passed on each of Node 20.0 and 22.13; four Windows-only tests skipped locally. Original-Python policy comparisons and 1,350 Windows path comparisons per runtime matched.
• SDK/MCP types, formatting, Rust checks for both Windows targets, Ruff, and portable source checks passed.
• The actual tarball passed installed CLI, SDK, MCP, credential-locking, and nested-worker checks. Its extracted helper resolved policies and listed inventory on both Node versions with an empty PATH.
• Two full SDK runs passed: 2,171 passed, 45 skipped, zero failures per run (seeds 12345 and 1197252949).
• Three fresh independent reviews and a separate verification pass found no actionable issues on the final commit.

Risk and rollout

The helper entrypoint changes from the Python script to the shared launcher; repository callers are updated together. Other Python helpers remain until their migration slices land. The package uses the current verified native artifacts. Actual Windows execution of the new policy helper is a hosted CI gate and was not run on the local Linux host.

Public disclosure review

• No customer, partner, prospect, or user identities, data, or identifying details are included.
• No credentials, personal data, private source, scan findings, or nonpublic links or tickets are included.
• I reviewed the branch name, title, description, commits, changes, comments, logs, screenshots, attachments, and links for public disclosure.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
🔒 Security Review	✅ Completed 2026-09-03T03:39:47.099565Z	1eb78b2	PR opened

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