Per-Step Data & Individual Fin Control

[MyroslavRepin]

Feature Request: Per-Step Data & Individual Fin Control

Goal: Allow access to rocket state and control of each fin at every simulation step.

Description:
Enable a callback or loop hook so users can read orientation (yaw, pitch, roll) and update individual fin angles dynamically during the simulation.

Example Usage:

def step_callback(state):
    # access state.yaw, state.pitch, state.roll
    fin1.angle = ...
    fin2.angle = ...

for t in sim_steps:
    step_callback(rocket.get_state())
    rocket.update_dynamics()

[Gui-FernandesBR]

duplicated #915