Added config and setup(), handler(), Add which-key support, allow items= to be a function, more README, add some types, automatic filetype items

[Kamilcuk]

Hi:

• Create require("menu").config require("menu").setup() for configuration
• Added require("menu").handler() that does the same as from README.
• I created which-key menu to draw a full recursive menu starting from mapleader, which I think will be the most useful for users.
• items= can now be a function, like items = function() require("menus.which-key") end. This is done to lazy-load the items when they are opened. There is no need to load every submenu from the start.
• Added menus/fs/ directory that has filetype specific menus and added support in handler() to detect them.
• Added stylua.toml. I aimed for style closest to the existing formatting style.

Example which-key example of 4 menus:

[siduck]

this is getting complex, i wanted default file to just be an example

[Strongsloth]

would be cool, but is it good performance wise?

[Kamilcuk]

hi @Strongsloth The which-key menu opens instantly for me in astronvim if that's what you are asking.

[Strongsloth]

yeah

[siduck]

whichkey doesnt open instantly for the first time in nvchad because

NvChad/NvChad#3036

[Strongsloth]

oh so that's why when I press the <Leader> then a prefix such as db or dd it doesn't instantly show whickkey