What happened?

When opening a scenario with 2000 trains, the front tries to load the full list of conflicts, without any pathfinding/simulation being in cache, which brings the back to its knees.

Seeing that my page wasn't loading, I refreshed several times, piling the requests for list of conflicts, leading to crashing the back over and over

What did you expect to happen?

I expected the front to load the largest data last, in order to not prompt users to refresh their page when large computations are requested

How can we reproduce it (as minimally and precisely as possible)?

1. Open a scenario
2. Look at requests

Having a large timetable may help (for example the one in https://rec-osrd.reseau.sncf.fr/operational-studies/projects/134/studies/863/scenarios/1870), because the api's response will be way slower

On which environments the bug occurs?

Recette, Preprod (SNCF)

On which browser the bug occurs?

Firefox

OSRD version (top right corner Account button > Informations)

staging 770a507