Refactoring of taxonomy and evaluating nodes

[Invizory]

• Consider removing useless generic parameters like Object and Property in MemberExpression<Object, Property extends PropertyKey>.
• Consider simplifying *Description.
• Consider adding more methods to EvaluatedExpressions (like typeof and delete).
• Consider adding wrap to EvaluatedExpressions.
• Consider renaming Watchable to Boxed or Wrapped.