feat add ZoomPlugin

[HoodyHuo]

Short description

Add zoom plugin ,which implements waveform zoom operation via mouse wheel.

Implementation details

By calculating the scaled ratio and scroll position based on the audio time at the mouse's location, the current zoom level, and the width of the div container, we can then adjust the zoom level of wavesurfer and control scrolling

How to test it

Screenshots

Checklist

• This PR is covered by e2e tests
• It introduces no breaking API changes

[katspaugh]

A nice plugin with a clear purpose! ❤️

[HoodyHuo]

I need to do anything else? This is my first PR.

[katspaugh]

Yes, I'd like the comments I left addressed.

[katspaugh]

The code looks good!
It would be nice to also add an example in the examples folder.

[HoodyHuo]

The code looks good! It would be nice to also add an example in the examples folder.

nice, I will add one tomorrow.

[katspaugh]

Awesome, thank you!

[Serek16]

@katspaugh would be nice to have that example on the website.

[katspaugh]

Feel free to add it

[Serek16]

I meant on wavesurfer.xyz/examples/. And if possible, I haven't found a way to do it.

[katspaugh]

They are sourced from https://github.com/katspaugh/wavesurfer.js/tree/main/examples

Edit:
Ah, I see, the example js is already there: https://wavesurfer.xyz/examples/?zoom-plugin.js. I'll link it from the sidebar as well.