[MIG] bemade_fsm to 18.0
Aside from fixing standard 17.0..18.0 stuff and fixing XML ID
references:
1. **Remove `_get_closed_stage_by_project()`**: This method is
obsolete - it was copied from base FSM but no longer exists in
18.0. Base system now uses `is_closed` field.
2. **Implement State Propagation**: Enhance the `write()` method
to propagate done/cancelled states to child tasks using `is_closed` field logic.
3. **Test Task Creation**: Thoroughly test the custom task creation logic
against base 18.0
All 56 tests are passing.
1. Site contacts and work order contacts now get set on create and write
of all FSM project tasks. If the task has no parent_id, it will try
to set them from the sale order if it has one. Otherwise, they are
simply inherited from the parent.
2. Changing the site or work order contact on a task no longer feeds
back to the sale order.
3. Changing the site or work order contacts on a parent task propagates
the change to its subtasks.
