Change audio cursor with different color and make it bolder

**Is your feature request related to a problem? Please describe.**
Currently, if you see it's quite difficult to distinguish the audio cursor with the region boundary in the audio pane. Can we change the color for the cursor and thickness as well?

**Describe the solution you'd like**
The solution should be able to configure the color and thickness from the labeling template. Or maybe we can have hardcoded value as well