refactor!: move extras in seperate directories

lua/tokyonight/extra/init.lua

@@ -2,6 +2,7 @@ local M = {}
 
 local function write(str, fileName)
   print("[write] extra/" .. fileName)
+  vim.fn.mkdir(vim.fs.dirname("extras/" .. fileName), "p")
   local file = io.open("extras/" .. fileName, "w")
   file:write(str)
   file:close()
@@ -38,7 +39,7 @@ function M.setup()
     for style, style_name in pairs(styles) do
       config.setup({ style = style })
       local colors = require("tokyonight.colors").setup({ transform = true })
-      local fname = extra .. "_tokyonight_" .. style .. "." .. ext
+      local fname = extra .. "/tokyonight_" .. style .. "." .. ext
       colors["_upstream_url"] = "https://github.com/folke/tokyonight.nvim/raw/main/extras/" .. fname
       colors["_style_name"] = "Tokyo Night" .. style_name
       write(plugin.generate(colors), fname)