🧷 refactor: Require a Mounted Steer Host Instead of a Module Default

[berry-13]

Summary

useSteerHost fell back to a host registered with setDefaultSteerHost, which the app called as an import side effect of Providers/SteerHostContext.tsx. That is a module-level mutable default: a steer hook rendered outside SteerHostProvider silently worked through whatever the last import registered, which is the reach-for-global pattern the package should not extend.

This removes setDefaultSteerHost and its import-time call. useSteerHost now throws a named error when no provider is mounted. Every real render path of the steer hooks is under routes/Root.tsx, which already mounts SteerHostProvider (the share view and the standalone auth routes render none of them), so the app is unaffected. Client specs that render the steer hooks mount the app host through a small SteerHostTestProvider in client/test/steerHost.tsx, and the package's host spec covers the missing-provider error.

Part of the stack that moves the steer hooks into the chat package; base is the previous link.

Type of change

• Refactor

Testing

Tested environments/configuration:

Local jest and typecheck; no runtime configuration matters for this change.

Automated tests:

• cd client && npx jest src: the full client suite, 791 suites, 12,048 tests pass.
• cd packages/chat && npx jest src/react/steer: host spec covers the nearest provider and the missing-provider error.
• npx tsc --noEmit for client and packages/chat: clean. ESLint, Prettier and import sorting clean on every changed file.

Screenshots / recordings

No user-facing change.

Risk / compatibility

Low. A steer hook rendered outside the provider now fails loudly instead of using a registered default; the full client suite and a grep of render paths found none outside Root.

Checklist

• I reviewed my own changes
• Existing relevant tests pass
• The change does not introduce new warnings or errors

[chatgpt-codex-connector]

Codex Review Summary

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

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-18T15:45:54.793923Z	5e52d8d	New commits
🔒 Security Review	✅ Completed 2026-10-15T16:18:01.301823Z	ae8fa8b	Draft marked ready

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