Address PR #209 review.
- use-open-ai-chat.ts: call setWindowOpen(true) before awaiting
getBoundChat so the header button feels instant on slow connections;
the chat switch (setActiveChatId/setDraft/setSelectedRoleId) is applied
after the round-trip resolves. Also drop the redundant no-op
setWindowOpen(true) in the already-open branch (bare early return).
- CHANGELOG.md: document the header AI-chat button auto-opening the
latest chat bound to the current document under [Unreleased]/Added.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>