fix: action mt so we can again concat actions from two different tables (#1143)

* fix: action mt so we can again concat actions from two different tables

- without actually changing the public interface
- without having a local table that keeps track of all actions

* this should clear actions now

we never actually called this function which is kinda a problem because
we never cleaned up previous mapping stores.
We can also make a better mappings store which has access to the keys
sequences which would help the showing actions part

* bugfix

* that should now clear everything

only tests left i think

* more tests

* cleanup

* hack: make sure all actions get cleared

lua/telescope/pickers.lua

@@ -8,7 +8,6 @@ local channel = require("plenary.async.control").channel
 local popup = require "plenary.popup"
 
 local actions = require "telescope.actions"
-local action_set = require "telescope.actions.set"
 local config = require "telescope.config"
 local debounce = require "telescope.debounce"
 local deprecated = require "telescope.deprecated"
@@ -48,12 +47,6 @@ function Picker:new(opts)
     error "layout_strategy and get_window_options are not compatible keys"
   end
 
-  -- Reset actions for any replaced / enhanced actions.
-  -- TODO: Think about how we could remember to NOT have to do this...
-  --        I almost forgot once already, cause I'm not smart enough to always do it.
-  actions._clear()
-  action_set._clear()
-
   deprecated.options(opts)
 
   local layout_strategy = get_default(opts.layout_strategy, config.values.layout_strategy)
@@ -1304,6 +1297,7 @@ function pickers.on_close_prompt(prompt_bufnr)
   end
 
   picker.close_windows(status)
+  mappings.clear(prompt_bufnr)
 end
 
 function pickers.on_resize_window(prompt_bufnr)