feat: make buffer cleanup delay configurable (#191)

lua/oil/config.lua

@@ -34,6 +34,10 @@ local default_config = {
   trash_command = "trash-put",
   -- Selecting a new/moved/renamed file or directory will prompt you to save changes first
   prompt_save_on_select_new_entry = true,
+  -- Oil will automatically delete hidden buffers after this delay
+  -- You can set the delay to false to disable cleanup entirely
+  -- Note that the cleanup process only starts when none of the oil buffers are currently displayed
+  cleanup_delay_ms = 2000,
   -- Keymaps in oil buffer. Can be any value that `vim.keymap.set` accepts OR a table of keymap
   -- options with a `callback` (e.g. { callback = function() ... end, desc = "", mode = "n" })
   -- Additionally, if it is a string that matches "actions.<name>",