[codex] Add init-first onboarding flow

[jasonacurry]

Summary

• add xerg init, xerg connect, and xerg mcp-setup as the new local-first onboarding path
• extend shared auth resolution and login reuse so hosted follow-up uses the same credential flow and cached push logic
• update CLI help, tests, docs, npm README, and skill docs to reflect the init-first story and paid-feature boundaries

Why

• reduce the time to first local audit result
• keep hosted setup optional while disclosing paid boundaries clearly
• align the CLI, docs, npm package, and skill surfaces around the same onboarding flow

Validation

• pnpm lint
• pnpm test
• pnpm typecheck

[mintlify]

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Project	Status	Preview	Updated (UTC)
xerg	🟢 Ready	View Preview	Apr 13, 2026, 4:53 PM

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