3df7cc01ea
Adds WhiteboardPayload wire-format variant to MessagePayload/ParsedMessagePayload, creates the whiteboards.ts CRUD wrapper (createWhiteboard, listWhiteboardStrokes, insertWhiteboardStroke, clearWhiteboardStrokes), writes 5 unit tests (38/38 pass), re-exports from chat/index.ts, and registers conversation_whiteboards + whiteboard_strokes in packages/db-types so typecheck passes cleanly. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>