Minor fixes and changes to `geometry.pyi` stub file

[aatle]

Improved some stuff.

• Change has-attribute protocols to use properties (to fix typing problems)
• Remove type unions _CanBeCircle, _CanBeLine. These internal types provide little benefit, and a similar union _CanBeRect was removed previously.
  • This has one minor effect: the circle attribute can now be another object with a circle attribute, recursively (which reflects actual implementation)
• Rename _CircleValue -> _CircleLike, _LineValue -> _LineLike, to be consistent with RectLike, adhere to naming scheme.
• Fix name typo _HasCirclettribute -> _HasCircleAttribute
• Remove redundant Vector2 type from _CanBeCollided. Vector2 is clearly implied by Point.
• Mark Circle.contains(shape) parameter positional-only
• Format