narval #3553211 Narval should use new recipe format [validation pending]

The new format replaces the graph-based recipes by Python scripts.

prioritynormal
typeenhancement
done in4.0.0
load10.000
load left0.000
closed by<not specified>
patch[doc] write some documentation (related to #3553211, #2059933) [applied][migration] set unset script recipes to a constant noop (related to #3553211) [applied]