Sonification pulse oscillators override an explicit zero width

Expected behaviour

A public SynthPatch pulse oscillator configured with pulseWidth: 0 should preserve that explicit value. The implementation already accepts and clamps pulse width at a minimum of zero.

Actual behaviour

Initialization uses a truthy fallback, replacing zero with the default 0.5.

Live demo with steps to reproduce

1. Construct new Highcharts.sonification.SynthPatch(context, { oscillators: [{ type: 'pulse', pulseWidth: 0 }] }).
2. Inspect the created oscillator's runtime pulse width.
3. Observe 0.5 instead of 0.

Product version

Current main