refactor(files): remove nvim-tree and replace with mini.files for file exploration

lua/core/options.lua

@@ -60,9 +60,6 @@ for k, v in pairs(options) do
     vim.opt[k] = v
 end
 
-vim.g.loaded_netrw = 1
-vim.g.loaded_netrwPlugin = 1
-
 vim.opt.path:append({ '**' })
 vim.opt.shortmess:append({ W = true, I = true, c = true }) -- disable greeting