Function solve_float_epoch 

pub fn solve_float_epoch(
    source: &dyn ObservableEphemerisSource,
    epoch: FloatEpoch,
    initial_state: FloatState,
    config: FloatSolveConfig,
) -> Result<FloatSolution, FloatSolveError>

Solve one float PPP epoch with the same state shape as Sidereon’ historical single-epoch API: receiver position, one receiver clock, and one ambiguity per observation.