- Implemented union in OrbitalElements (semi_major_axis | semi_latus_rectum)
- Updated config_loader to validate parabolic vs elliptical/hyperbolic orbits
- Fixed orbital_mechanics.cpp parabolic case to use semi_latus_rectum
- Updated parabolic_comet.toml to use correct orbital parameters
- Updated validation logic for both bodies and spacecraft
- Created docs/parabolic_union_implementation.md with full implementation plan
- Updated docs/unified_orbital_elements_plan.md to mark phases 7-9 complete
Note: Parabolic orbit test velocity tolerance check fails due to test expecting
velocity at 1 AU, but config has comet at perihelion (0.5 AU).
Position and velocity are mathematically correct, energy is ~0.
- Replace position/velocity with orbit table parsing
- Parse all orbital element fields with defaults
- Support altitude convenience field for semi_major_axis
- Add validation for orbital elements
- Remove manual position/velocity calculation from loader
- Build succeeds (expected unused function warning)
- Rename CelestialBody/Spacecraft position/velocity to global_*
- Add OrbitalElements struct to both bodies and spacecraft
- Rename old OrbitalElements to OrbitalMetrics (for output/analysis)
- Update all references throughout codebase
- Preserve parent_index in outer structs (not in OrbitalElements)
- Build succeeds with only unused variable warning