Added new collaborator, document, and dettings APIs including DELETE, GET, PATCH, and POST methods for managing whiteboards, collaborators, documents, and share settings.

New endpoints released for collaborators, documents and settings


## Added

New **Collaborator** APIs:

- `DELETE /v2/whiteboards/{whiteboardId}/collaborator/{collaboratorId}`
- `GET /v2/whiteboards/{whiteboardId}/collaborator`
- `PATCH /v2/whiteboards/{whiteboardId}/collaborator`
- `POST /v2/whiteboards/{whiteboardId}/collaborator`

New **Document** APIs:

- `POST /v2/whiteboards`
- `PUT /v2/whiteboards/{whiteboardId}`
- `GET /v2/whiteboards`
- `GET /v2/whiteboards/{whiteboardId}`
- `DELETE /v2/whiteboards/{whiteboardId}`

New **Settings** API:

- `PATCH /v2/whiteboards/{whiteboardId}/share_setting`
