feat(util.mini): follow the user's mappings instead of hardcoded values (#4043)

Because I use the Colemak-DH keyboard layout, I have mapped 'i' to 'h'.
Therefore, the current mini.ai which_key prompts are inconsistent with
my keymap.


## Description

The names and prefixes used in mini.ai_whichkey() are hardcoded and
should follow the user's mappings.

## Related Issue(s)

No

## Screenshots

No

## Checklist

- [ x ] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

---------

Co-authored-by: Folke Lemaitre <folke.lemaitre@gmail.com>

lua/lazyvim/plugins/coding.lua

@@ -171,9 +171,6 @@ return {
     "echasnovski/mini.ai",
     event = "VeryLazy",
     opts = function()
-      LazyVim.on_load("which-key.nvim", function()
-        vim.schedule(LazyVim.mini.ai_whichkey)
-      end)
       local ai = require("mini.ai")
       return {
         n_lines = 500,
@@ -197,6 +194,14 @@ return {
         },
       }
     end,
+    config = function(_, opts)
+      require("mini.ai").setup(opts)
+      LazyVim.on_load("which-key.nvim", function()
+        vim.schedule(function()
+          LazyVim.mini.ai_whichkey(opts)
+        end)
+      end)
+    end,
   },
 
   {