fix: allow the user to set the default todo state

As the order of the org_todo_keywords define the order of the todo in
the agenda, a user may want to have a default TODO state different than
the first one in the org_todo_keywords list

lua/orgmode/config/defaults.lua

@@ -7,6 +7,7 @@ local DefaultConfig = {
   org_agenda_files = '',
   org_default_notes_file = '',
   org_todo_keywords = { 'TODO', '|', 'DONE' },
+  org_todo_default_state = nil,
   org_todo_repeat_to_state = nil,
   org_todo_keyword_faces = {},
   org_deadline_warning_days = 14,

lua/orgmode/org/mappings.lua

@@ -739,7 +739,11 @@ function OrgMappings:insert_heading_respect_content(suffix)
 end
 
 function OrgMappings:insert_todo_heading_respect_content()
-  return self:insert_heading_respect_content(config:get_todo_keywords():first_by_type('TODO').value .. ' ')
+  local first_todo_keyword = config.org_todo_default_state or config:get_todo_keywords():first_by_type('TODO').value
+  if not first_todo_keyword then
+    error('No default TODO keyword found')
+  end
+  return self:insert_heading_respect_content(first_todo_keyword .. ' ')
 end
 
 function OrgMappings:insert_todo_heading()