Intinerary from buffer stop to buffer is allowed in infra editor but creates an invalid infra when you try to use it in a simulation

In the infrastructure editor window I can't see any issue with my infrastructure:

When trying to run a simulation on it:

It may be related to the fact that I have created itineraries from buffer stops to buffer stops and this is not allowed by core I think

To reproduce you can open : https://rec-osrd.reseau.sncf.fr/operational-studies/projects/3/studies/44/scenarios/257 and https://rec-osrd.reseau.sncf.fr/editor/8

Core response:

{"status":400,"type":"infra_loading:hard_error","context":{"source_operation":"BUILDING_BLOCKS","url":"http://osrd-rec-core.osd-rec01.svc.cluster.local/infra_load"},"message":"hard error while loading new infra"}

Version: staging 5a4c741

Start by reproducing the issue with the linked scenario and infrastructure editor, then inspect the core response from the /infra_load operation. Trace how buffer-stop-to-buffer itineraries are accepted by the editor and rejected during simulation. Done means the invalid infrastructure is prevented or the simulation no longer fails, with coverage for this itinerary case.