typing improvements

[spyoungtech]

• mouse_position, get_mouse_position, pixel_search, and image_search now return a Coordinates named tuple (typing.NamedTuple) type instead of just a plain tuple[int, int].
• Refactored types shared between sync and async into a common, internal, _types module.
• The Position type is now created using typing.NamedTuple rather than collections.namedtuple.
• Exposes more types directly via __init__.py so they can be imported without reaching into internal modules.

[coveralls]

coverage: 77.41% (+0.1%) from 77.301% when pulling 913955264fa0ad8919eda3c3fe5c051cc5422782 on typing-improvements into 64838efae230e11a82b61c11357d4b2a9f4c6845 on main.