internal/

Package missions defines pass/fail objectives evaluated against the live sim state each Tick.

Package physics implements the spacecraft propagation layer: state vectors, integrators (Verlet + RK4), and patched-conic SOI handling.

Package planner implements trajectory prediction (predictor) and stubs for Phase 3 maneuver-library work (hohmann, lambert) that slip past v0.1.

Package render holds the visual constant tables shared across screens — body color palette, UI tier colors for status / nodes / trajectory.

Package save persists and restores the simulation World as JSON.

Package sim — v0.11.0+ launch-trail breadcrumb buffer.

Package spacecraft holds the Spacecraft type and its mutable runtime state (current primary + state vector + fuel).