Add typings for LSP

[WhyNotHugo]

With these changes, lua-language-server will show type hints for the config and all its fields.

This is strongly based on the typings provided by @zorgick in #563. I omitted the defaults. When putting the typing defitions together with the declaration of the default instance, the LSP will use its values as default values.

Closes: https://github.com/nvim-lualine/lualine.nvim/issues/563 Co-Authored-By: @zorgick

[WhyNotHugo]

@zorgick: I'm including you as co-author since I mostly copy-pasted your example into the right place. Let me know if you'd rather not be included.

[shadmansaleh]

Some of those hints might require update since the issue is quite old . I'll look at it later after I get #736 working properly.

[shadmansaleh]

Can you add support for the newly added options in #736

[WhyNotHugo]

Updated and rebased.