OpenTOP 2.6.0

OpenTOP 2.6.0 uses continuous, piecewise-linear Mach, vertical-speed, and heading controls. Controls now change gradually across each interval, including an independent arrival control. Trajectory DataFrame columns and boundary-row counts remain unchanged.

• Correct state and time initialization, including collocation-point guesses. One-time fuel, contrail, and climate comparisons showed fewer iterations with essentially unchanged objectives after this initialization fix.
• Enforce Cruise performance constraints at boundaries and internal collocation points.
• Add optional CompleteFlight.trajectory(path_constraint_points=[(interval, tau), ...]) for extra force and energy constraint checks inside intervals.
• Update the full-flight numerical regression baseline after mesh and targeted-constraint validation, retaining the existing 1% tolerance.

Validation: all 272 tests passed, including contrail and climate objectives. Formatting, lint, type, package-build, and isolated Python 3.11 installation checks passed.

Path constraints are enforced at finite points. Extra points must be supplied explicitly; automatic path refinement is not included. Solver convergence does not guarantee feasibility everywhere between checked points.