replace enums with named maps

lua/nvim-tree/enum.lua

@@ -1,24 +1,5 @@
 local M = {}
 
----Setup options for "highlight_*"
----@enum HL_POSITION
-M.HL_POSITION = {
-  none = 0,
-  icon = 1,
-  name = 2,
-  all = 4,
-}
-
----Setup options for "*_placement"
----@enum ICON_PLACEMENT
-M.ICON_PLACEMENT = {
-  none = 0,
-  signcolumn = 1,
-  before = 2,
-  after = 3,
-  right_align = 4,
-}
-
 ---Reason for filter in filter.lua
 ---@enum FILTER_REASON
 M.FILTER_REASON = {