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>
packages/shared/src/index.ts and all sub-modules used .js extensions on
relative imports (e.g. './admin/index.js') pointing at .ts source files.
TypeScript with moduleResolution: "Bundler" doesn't need them, and
Metro's eager exporter (used for preview / production builds) reads
them literally and fails — only the dev-server Metro fell back to .ts.
Workspace typecheck remains 8/8 green; Vite and TS Bundler resolution
already accept both styles, so desktop is unaffected.