Fix invalid SVG error when using special char in layer lable

[HelloThisIsFlo]

Hi @caksoylar,

This is a super quick PR to fix an issue with string escape. I have a layer called <^v> (my nav layer), and it causes issues with the draw function.

The draw function would not see any error, but the resulting SVG is invalid. This is the error

error on line 2462 at column 50: Unescaped '<' not allowed in attributes values

The fix was super quick, I just used your pre-existing escape function to escape the name. I tested it and it works as expected.

One thing to note: I couldn't see where the layer styling class is actually used 🤔. So it is now correctly escaped, but it appears the classname isn't used anywhere. So, either it is indeed not used, and that's fine. Or it is used somewhere and I missed it. In which case, let me know where and I'll update the PR.

Thank you for your work 🙏

[caksoylar]

Thank you, good fix! The class isn't used by keymap-drawer by default but it allows people to use it in their CSS (e.g. in svg_extra_style), if they want to do any per-layer styling.