Update trajectory figures

[teubert]

Update the way trajectory figures are generated to be a little more general.

The function in UAVModel still works the same as before, but now theres a function to explore a reference trajectory and it can be used outside of the UAVModel. This is important for when it's used with prog_server

[github-actions]

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[codecov-commenter]

Codecov Report

Attention: 34 lines in your changes are missing coverage. Please review.

Comparison is base (bda3c9e) 83.41% compared to head (0ff35ab) 83.27%.

Files	Patch %	Lines
src/progpy/utils/traj_gen/trajectory.py	24.13%	22 Missing ⚠️
...c/progpy/models/aircraft_model/small_rotorcraft.py	14.28%	12 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              dev     #136      +/-   ##
==========================================
- Coverage   83.41%   83.27%   -0.14%     
==========================================
  Files         100      100              
  Lines       10461    10488      +27     
==========================================
+ Hits         8726     8734       +8     
- Misses       1735     1754      +19     

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[kjjarvis]

Nice improvement of plotting functionality