feat: allow register_ui_select via setup options

This allows configuration in e.g. lazy.nvim to simply be:

```lua
opts = {
  ui_select = true,
},
```

instead of needing to override the setup() call.

Author: netmute

OPTIONS.md

@@ -137,6 +137,14 @@ Example, opening a floating help window at the top of screen with single border:
     })
 ```
 
+#### setup.ui_select
+
+Type: `boolean|table|function`, Default: `false`
+
+Register fzf-lua as the UI interface for `vim.ui.select` during `setup`.
+
+When set to a table or function, the value is passed to `register_ui_select`.
+
 ---
 
 ## Global Options

doc/fzf-lua-opts.txt

@@ -1,4 +1,4 @@
-*fzf-lua-opts.txt*       For Neovim >= 0.8.0      Last change: 2025 October 24
+*fzf-lua-opts.txt*       For Neovim >= 0.8.0      Last change: 2026 January 03
 
 ==============================================================================
 Table of Contents                             *fzf-lua-opts-table-of-contents*
@@ -175,6 +175,16 @@ border:
         })
 <
 
+                                                                              
+setup.ui_select                                 *fzf-lua-opts-setup.ui_select*
+
+Type: `boolean|table|function`, Default: `false`
+
+Register fzf-lua as the UI interface for `vim.ui.select` during `setup`.
+
+When set to a table or function, the value is passed to `register_ui_select`.
+
+
 ------------------------------------------------------------------------------
 GLOBAL OPTIONS                                   *fzf-lua-opts-global-options*
 
@@ -1626,7 +1636,7 @@ Neovim's autocmds
 
 
 
-undo                                                       *fzf-lua-opts-undo*
+undotree                                               *fzf-lua-opts-undotree*
 
 History undo tree
 

lua/fzf-lua/init.lua

@@ -232,6 +232,12 @@ function M.setup(opts, do_not_reset_defaults)
   config.setup_opts = opts
   -- setup highlights
   M.setup_highlights()
+  -- opt-in register ui.select via setup
+  if opts.ui_select then
+    M.register_ui_select((type(opts.ui_select) == "table" or type(opts.ui_select) == "function")
+      and opts.ui_select or nil,
+      true) -- silent
+  end
 end
 
 M.redraw = function()