New typing support

[sergey-bondarenko-qs]

• Dropped support of Python earlier than 3.11
• Dropped support of Django earlier than 4.2
• Dropped support of SQLAlchemy earlier than 1.4
• Added support of Python 3.13
• Added tests of new typing features for event system
• Reviewed new typing-related things since Python 3.8:
  • Added support of Union[A, B] → A | B
  • Added support of List[T] → list[T], Dict[K, V] → dict[K, V], etc.
  • Reviewed Never and NoReturn types - they are only for forever-looping functions, no sense to add their support
  • Reviewed Self return type support - not suitable for endpoints, they do not return classes
  • Added test for TypeAlias
  • Reviewed TypeGuard - not suitable for endpoints
  • Reviewed LiteralString - not suitable for endpoints, they usually return strings
  • Reviewed Concatenate - not suitable for endpoints
  • Added test for TypedDict