narval #4128903 narval commands should take only an instance id and the eid of the task to run [validation pending]

this goes with some simplifications in the URL management in narval, which is now quite obfuscated for no reason.

prioritynormal
typetask
done in4.1.0
load1.000
load left0.000
closed by#290087b9fa97 [bot] refactor the Plan manipulation machinery (closes #4128903)
patch[bot] refactor the Plan manipulation machinery (closes #4128903) [applied]