ENH: Simulation Save and Load in JSON Files

[phmbressan]

Pull request type

• [X] Code changes (bugfix, features)

Checklist

• [X] Tests for the changes have been added (if needed)
• [ ] Docs have been reviewed and added / updated
• [X] Lint (black rocketpy/ tests/) has passed locally
• [X] All tests (pytest tests -m slow --runslow) have passed locally
• [ ] CHANGELOG.md has been updated (if relevant)

New behavior

This PR improves rocketpy encoding and introduces decoding functionalities. The way this works is:

• If the is a to_dict or from_dict method, they are used to perform the (de)encoding;
• Otherwise, a default encoding of all vars() and constructor based decoding is done.

Breaking change

• [ ] Yes
• [X] No

Additional information

PR #679 should be merged first.

Here are some of the steps that could be improved:

• [ ] Verify why the test for hybrid motor flight requires higher tolerances;
• [ ] Test if all of the atmospheric models of Environments can be decoded without requiring re-read of files or API;
• [ ] Evaluate whether we should encode outputs or only the minimum required information to decode the class from its init;
• [ ] (Optional) Expand implementation to AirBrakes + Controllers and new classes.

Some important remarks:

• The simple getting started simulation is essentially identical comparing the store & load, the only difference is the random lag and noise from Parachute class. I could not found a simple solution to reset those and always get the same results.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 81.19891% with 69 lines in your changes missing coverage. Please review.

Project coverage is 76.38%. Comparing base (7c18881) to head (5d1c585). Report is 3 commits behind head on enh/sim-encoding.

Files with missing lines	Patch %	Lines
rocketpy/environment/environment.py	63.82%	17 Missing :warning:
rocketpy/_encoders.py	81.25%	9 Missing :warning:
rocketpy/motors/tank.py	80.48%	8 Missing :warning:
...ocketpy/rocket/aero_surface/fins/free_form_fins.py	33.33%	6 Missing :warning:
rocketpy/motors/tank_geometry.py	83.87%	5 Missing :warning:
...cketpy/rocket/aero_surface/fins/elliptical_fins.py	37.50%	5 Missing :warning:
rocketpy/simulation/flight.py	37.50%	5 Missing :warning:
rocketpy/motors/motor.py	76.47%	4 Missing :warning:
rocketpy/rocket/components.py	42.85%	4 Missing :warning:
rocketpy/mathutils/vector_matrix.py	66.66%	3 Missing :warning:
... and 2 more

Additional details and impacted files

@@                 Coverage Diff                  @@
##           enh/sim-encoding     #695      +/-   ##
====================================================
+ Coverage             76.37%   76.38%   +0.01%     
====================================================
  Files                    94       94              
  Lines                 11343    11341       -2     
====================================================
  Hits                   8663     8663              
+ Misses                 2680     2678       -2     

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[Gui-FernandesBR]

@phmbressan , as previously discussed, can you leave only one of the #679 and #695 open please?