[ADD] real_estate: Property maintenance requests and validations

- Created maintenance request model linked to property
- Added status workflow
- Validated approved maintenance cost
- Computed total maintenance cost on property
- Blocked property sale if any maintenance request is not done
- Blocked deletion of properties and maintenance when maintenance is not done

Author: rugot-odoo

real_estate/models/real_estate_properties.py

@@ -129,7 +129,7 @@ def _unlink_if_accepted_offer(self):
 
     def action_cancel(self):
         if self.stage == 'sold':
-            raise UserError("A sold property cannot be cancelled")
+            raise UserError("A sold property cannot be cancelled.")
         self.stage = 'cancelled'
 
     def action_sold(self):

real_estate/models/real_estate_properties_maintenance_request.py

@@ -25,4 +25,4 @@ def _check_cost_on_accepted_status(self):
     def _unlink_if_maintenance_request_not_done(self):
         maintenace_request = self.filtered_domain([('status', '!=', 'done')])
         if maintenace_request:
-            raise UserError("Can't delete an active Maintenance Request Record!")
+            raise UserError("Can't delete an active Maintenance Request Record.")