<Anchor> `edgeLabel` property doesn't seem to be reactive

[hopperelec]

Description

An edge's label does not react to changes if applied via an <Anchor>'s edgeLabel property. I also don't think it's possible to pass props to a custom Edge in order to customize the label that way. So, there is seemingly no way to update an edge label.

Reproduction

https://stackblitz.com/edit/svelvet-v9-kpweqo?file=src%2Froutes%2F%2Bpage.svelte

System information

System:
OS: Linux 5.0 undefined
CPU: (4) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
Memory: 0 Bytes / 0 Bytes
Shell: 1.0 - /bin/jsh
Binaries:
Node: 18.20.3 - /usr/local/bin/node
Yarn: 1.22.19 - /usr/local/bin/yarn
npm: 10.2.3 - /usr/local/bin/npm
pnpm: 8.15.6 - /usr/local/bin/pnpm

Additional information

No response

👨‍👧‍👦 Contributing

• 🙋‍♂️ Yes, I'd love to make a PR to fix this bug!