There's a closed pull request on the void-packages repository

snapcast: update to 0.28.0
https://github.com/void-linux/void-packages/pull/50290

Description:
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#### Testing the changes
- I tested the changes in this PR: **briefly**

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This release no longer bundles the pre-built [Snapweb](https://github.com/badaix/snapweb). When accessing the Snapweb page, you are now greeted with the following notice.
```
This is a placeholder for Snapweb, a web based control client and player for Snapcast.
To install Snapweb, please follow these steps:

    1. Download Snapweb on the Snapweb release page. You can either download
        * snapweb.zip and extract it on your Snapcast server machine, e.g. into /usr/share/snapserver/snapweb or
        * snapweb_x.y.z-1_all.deb and install it with sudo apt install ./snapweb_x.y.z-1_all.deb to /usr/share/snapweb
    2. Configure the document root (doc_root, see below) in the snapserver configuration file snapserver.conf — usually located in /etc/snapserver.conf — to the location where snapweb is extracted or installed.
    3. Restart Snapserver to activate the changes: sudo service snapserver restart
```
What should we do with Snapweb?
1. Leave the `snapcast` package as is and let the user fetch and extract the pre-built Snapweb as per instructions.
2. Fetch and install the pre-built Snapweb from the `snapserver` subpackage.
3. Create a new `snapweb` package and build it from source. The user can then install it if needed.