- Fix: Notion API's undocumented `description` of `SelectOption` added.
- New: Navigate pages using `parent` and `children`.
- Chg: Rename `parents` to `ancestors`.
- Fix: Wrong return value of PropertyType `Status.value`.
- Chg: Make `show` consistent for Page, View, PageSchema.
- Ref: Refactor `value` in `PropertyValue`.
- Ref: Reduce unnecessary funtionality of `Number`, use `value` instead.