feat: manage Codex native user-wide statusline

[pacphi]

Summary

• add ADR-0015 and explicit ak x statusline codex native|extended|off workflows
• manage only Codex's native [tui] status-line keys with explicit ownership, drift detection, sync, and uninstall support
• preserve unrelated TOML state and fail closed on ambiguous dotted, quoted, duplicate, or malformed forms
• model Claude command-backed and Codex built-in status-line capabilities separately
• document presets, scope, limitations, upgrading, and troubleshooting

Safety

• narrow backup-first atomic updates to ~/.codex/config.toml
• no mutation without explicit opt-in
• user-modified managed values survive off and uninstall
• ownership is retained when safe removal cannot parse the file
• no claim of Ruflo/SONA/AQE rich-renderer parity inside Codex

Validation

• pnpm run check
• full TypeScript, ESLint, Markdown lint, build/package, coverage, and test gates
• independent Ruflo swarm architecture, implementation, and reviewer lanes