Function calculate_all_checked 

pub fn calculate_all_checked(
    peaks: &[f32],
    troughs: &[f32],
    switch_times: &[DateTime<Utc>],
    mv_sign_init: i8,
    direction: ControllerDirection,
    config: LoopConfig,
    pv_range: PvRange,
    template: &DcsTemplate,
    compat: TuningMathCompat,
) -> [CheckedTuningResult; 3]

Checked counterpart to calculate_all.

The legacy numeric functions remain available for parity/replay callers. Production persistence should use this entry point so a degenerate PV amplitude or any non-finite intermediate/final value becomes an explicit invalid result instead of reaching SQLite or PID write-back as NaN/infinity.