Attach documentation comments to function type definitions

[dev-alastair]

When type annotations are added to functions at the point of their definition, moonwave-style function documentation works as expected and appears in Signature Help. However, when a type is defined separately, the documentation does not appear.

This works:

This does not work:

(Note: I've tried removing the comment on the type or the function definition so there is only one documentation comment, and it still doesn't work).

It would be awesome for this to be fixed, but also for the LSP to accept documentation comments in both places (either on types or function definitions) to allow types and documentation to be defined in one place, and implementations to be defined in another. Thanks so much for your work!