#828 Status filter allowlists incomplete: 'orphaned' unfilterable; VALID_WORKFLOW_STATUSES dead constant missing 3 statuses

api/blueprints/v1/workflows.py:804 _status_keys = (completed,failed,running,pending,sleeping,paused,cancelled) — missing 'orphaned', so orphaned runs cannot be filtered in the list endpoint (invisible to status-filtered dashboard views). api/middleware/validators.py:16 VALID_WORKFLOW_STATUSES is missing paused/cancelled/orphaned AND appears to have zero usages (dead constant — wire it or delete it). Single source of truth suggestion: one canonical status tuple imported everywhere, asserted against the DB CHECK constraint in a test.