[IMP] status of contract on task, issue and sale order

- Task: https://www.odoo.com/web#id=9258&view_type=form&model=project.task&menu_id=3942&action=327
- Pad: https://pad.odoo.com/p/r.6XynUXUW6cac35nF
I have to show current contract status of project and if project have no customer and use_issues is disable so there is contract status are invisible for these reason i have used function fields no related fields.