Add support for selfserve_enabled lanes and synchronize behavior across tasks, sessions, and projections

- Introduced `selfserve_enabled` property for `department_lanes` with schema update, object properties, and associated methods/tests.
- Enhanced `selfserve_wash_flow` and session logic to respect lane self-serve settings, including block handling and task filtering.
- Updated API routes and Studio Graph projections to include `selfserve_enabled` in payloads and progress callbacks.
- Added unit tests for session statuses, lane configuration, and blocking behavior due to disabled self-serve settings.

openapi.yaml

@@ -15206,6 +15206,16 @@ components:
           type: array
           items:
             $ref: '#/components/schemas/SelfserveWashTaskSnapshot'
+        allowed_services:
+          type: array
+          items:
+            $ref: '#/components/schemas/SelfserveLaneService'
+        machine_available:
+          type: boolean
+        all_visible_questions_answered:
+          type: boolean
+        allowed:
+          type: boolean
         events:
           type: array
           items: