feat(event): add WillCreateFile, WillRemoveFile (#2273)

node. These are mostly going to be useful for implementing lsp file
operation actions.

Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/actions/fs/trash.lua

@@ -75,6 +75,7 @@ function M.fn(node)
         end
       end)
     else
+      events._dispatch_will_remove_file(node.absolute_path)
       trash_path(function(_, rc)
         if rc ~= 0 then
           notify.warn("trash failed: " .. err_msg .. "; please see :help nvim-tree.trash")