refactor harmonic motion spring

[ioxu]

• [x] convert all uses of CalcDampedSpringMotionParams() and calculate() to initialise() and calculate_c().
• [x] rename calculate_c() and references to calculate().
• [x] refactor calculate_v2() and caluclate_v3() to use _carry_velocity and DampenedSpringMotionParams class state.
• [x] update res://data/tests/harmonic_motion