feat(tutor): enable ai chat streaming

[drizco]

Warning!!

We have entered Pixel Lock for Hour of AI! All merges to the staging branch from Dec 2 through Dec 12 must go through live change review and be deemed critical for supporting the Hour of AI. External contributions will not be accepted at this time.

For non-critical changes, please change your base to staging-next and delete this warning. We will merge staging-next into staging on Dec 15, 2025.

Links

• Jira:

Testing story

Deployment strategy

Follow-up work

Privacy

Security

Caching

PR Creation Checklist:

• [ ] Tests provide adequate coverage
• [ ] Privacy impacts have been documented
• [ ] Security impacts have been documented
• [ ] Code is well-commented
• [ ] New features are translatable or updates will not break translations
• [ ] Relevant documentation has been added or updated
• [ ] User impact is well-understood and desirable
• [ ] Follow-up work items (including potential tech debt) are tracked and linked

[drizco]

@codex review