BUG: Flight class with Two Parachute and time_overshoot = False don't define some functions

[kevin-alcaniz]

Describe the bug

When simulating a Rocket with two Parachute instances in the Flight class and setting the time_overshoot attribute to False, several functions return undefined values: stability_margin, mach_number, free_stream_speed, stream_velocity_x, wind_velocity_x, and z.

As a result, running a MonteCarlo simulation with this setup raises a ValueError because these values can't be retrieved.

Interestingly, the issue doesn’t occur when the Rocket has only one of those Parachute instances — it works fine regardless of which one is used.

Could you take a look?