Remove unused solve_kepler_hyperbolic_with_prev() function

- Function was never called anywhere in the codebase
- Functionality now handled by propagate_orbital_elements() with proper Newton-Raphson iteration
- Removes dead code and simplifies the API

src/orbital_mechanics.cpp

@@ -88,24 +88,6 @@ double solve_kepler_hyperbolic(double mean_anomaly, double eccentricity) {
     return H;
 }
 
-double solve_kepler_hyperbolic_with_prev(double mean_anomaly, double eccentricity, double H_prev_guess) {
-    // Solve hyperbolic Kepler equation with a hint from previous H value
-    double H = H_prev_guess;
-
-    double H_iter = H + 2.0 * KEPLER_TOLERANCE;
-    int iterations = 0;
-
-    while (fabs(H - H_iter) > KEPLER_TOLERANCE && iterations < KEPLER_MAX_ITERATIONS) {
-        H_iter = H;
-        double sinh_H = sinh(H);
-        double cosh_H = cosh(H);
-        H = H - (H - eccentricity * sinh_H - mean_anomaly) / (1.0 - eccentricity * cosh(H));
-        iterations++;
-    }
-
-    return H;
-}
-
 double eccentric_to_true_anomaly(double eccentric_anomaly, double eccentricity) {
     if (fabs(1.0 - eccentricity) < 0.01) {
     // Near-parabolic: use cos/sin formulation to avoid numeric instability

src/orbital_mechanics.h

@@ -30,7 +30,6 @@ double solve_kepler_elliptical(double mean_anomaly, double eccentricity);
 
 // Hyperbolic Kepler equation solver: H - e·sinh(H) = M
 double solve_kepler_hyperbolic(double mean_anomaly, double eccentricity);
-double solve_kepler_hyperbolic_with_prev(double mean_anomaly, double eccentricity, double H_prev_guess);
 
 // Conversions between anomaly types
 double eccentric_to_true_anomaly(double eccentric_anomaly, double eccentricity);