Adds @vectorize-io/hindsight-chat, a wrapper for the Vercel Chat SDK
that gives any chat bot (Slack, Discord, Teams, etc.) long-term memory
via Hindsight. Includes withHindsightChat() handler wrapper with
auto-recall, auto-retain, and memoriesAsSystemPrompt() formatting.
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
