Parse function signature with untyped parameter

[inferrna]

Fixes lsp crash when parsing functions accepts parameter of any type ( like lobster_value_to_binary ) See also https://github.com/aardappel/lobster/blob/a7b921a4f3fd4d661bb05a84a218cae5047cd93f/dev/src/lobster/idents.h#L1365C1-L1372C2

[aardappel]

Thanks!