narval #3886459 some "REST" views does not return json on error [validation pending]

fire_transition, set_attributes, create_subentity, narval.pending-plans and the narval-file-append controller should return json whatever happens...

prioritynormal
typebug
done in4.1.0
load0.250
load left0.000
closed by#86b34d214028 [views] ensure "REST-like" views return JSON data (closes #3886459)
patch[views] ensure "REST-like" views return JSON data (closes #3886459) [applied]