v0.51.839

What's Changed

• Release v0.51.839 — incremental live streaming render, O(n²)→O(n) (#5466) by @nesquena-hermes in #5481
• perf(stream): render live prose incrementally, cut per-frame/per-token O(n^2) work (#5455) by @ai-ag2026 in #5466

Full Changelog: v0.51.838...v0.51.839