feat(clock): Clock out headline when it's marked as done

Closes #972

Author: kristijanhusak

lua/orgmode/events/listeners/clock_out.lua

@@ -0,0 +1,6 @@
+---@param event OrgTodoChangedEvent
+return function(event)
+  if event.headline:is_done() and not event.was_done and (event.old_todo_state and event.old_todo_state ~= '') then
+    event.headline:clock_out()
+  end
+end

lua/orgmode/events/listeners/init.lua

@@ -1,9 +1,11 @@
 local Events = require('orgmode.events.types')
 local AlignTags = require('orgmode.events.listeners.align_tags')
+local ClockOut = require('orgmode.events.listeners.clock_out')
 
 return {
   [Events.TodoChanged] = {
     AlignTags,
+    ClockOut,
   },
   [Events.HeadlineDemoted] = {
     AlignTags,

lua/orgmode/org/mappings.lua

@@ -477,10 +477,10 @@ function OrgMappings:_todo_change_state(direction)
   local repeat_note_template = ('%s- State %-12s from %-12s [%s]'):format(
     indent,
     [["]] .. new_todo .. [["]],
-    [["]] .. old_state .. [["]],
+    [["]] .. (old_state or '') .. [["]],
     Date.now():to_string()
   )
-  local repeat_note_title = ('Insert note for state change from "%s" to "%s"'):format(old_state, new_todo)
+  local repeat_note_title = ('Insert note for state change from "%s" to "%s"'):format(old_state or '', new_todo)
 
   if log_repeat_enabled then
     item:set_property('LAST_REPEAT', Date.now():to_wrapped_string(false))