Improve inference from return type annotations in completer (#14357) Addresses the issue of non-jedi completer not picking type annotations for `__init__()` brought up in https://github.com/ipython/ipython/issues/14336  Follow-up to https://github.com/ipython/ipython/pull/14185 Supports: - [x] `Annotated` - [x] `AnyStr` - [x] `Literal` - [x] `LiteralString` - [x] `NewType` - [x] `Optional` - [x] `Protocol` - [x] `Self` - [x] `TypeAliasType` (`type` keyword in Python 3.12+) - [x] `TypedDict` - [x] `TypeGuard` - [x] `Union` Limitations: - no type narrowing: ambiguous return types from `Union`, and `Optional` will always return all possible values - generics (`TypeVar` and `Generic`) are not support (except for `AnyStr`) - old style `TypeAlias` (deprecated in Python 3.12) is not supported