Function marker_hit

fn marker_hit(
    r: Response,
    m: &Marker,
    clip: Option<u64>,
    clip_start: f64,
    selected: &mut Option<u64>,
    start: &mut Option<(u64, Option<u64>)>,
    act: &mut Option<Act>,
    rename: &mut Option<(u64, String)>,
    seek: &mut Option<f64>,
    labels: &[Label],
)

Shared marker interaction (ruler flags and clip flags): click selects, double-click seeks, drag moves, right-click = Rename / Delete / Set label.