feat(pick): move pickers to extras (telescope still the default) (#3606)

## What is this PR for?

Refactoring of pickers in LazyVim:

- [x] telescope moved to extras
- [x] dressing was moved to the telescope extra. Not needed with fzf-lua
and noice
- [x] when none of the two is enabled, then telescope will be enabled
- [x] when using `:LazyExtras` to enable fzf-lua, the telescope spec
will never be parsed
- [x] when not using `:LazyExras`, the spec will be parsed, but one of
the two will be disabled.
- [x] only one picker extra can be used to prevent issues
- [ ] cleanup lsp keymaps

lua/lazyvim/plugins/ui.lua

@@ -34,24 +34,6 @@ return {
     end,
   },
 
-  -- better vim.ui
-  {
-    "stevearc/dressing.nvim",
-    lazy = true,
-    init = function()
-      ---@diagnostic disable-next-line: duplicate-set-field
-      vim.ui.select = function(...)
-        require("lazy").load({ plugins = { "dressing.nvim" } })
-        return vim.ui.select(...)
-      end
-      ---@diagnostic disable-next-line: duplicate-set-field
-      vim.ui.input = function(...)
-        require("lazy").load({ plugins = { "dressing.nvim" } })
-        return vim.ui.input(...)
-      end
-    end,
-  },
-
   -- This is what powers LazyVim's fancy-looking
   -- tabs, which include filetype icons and close buttons.
   {