serde support for Attributes

[ur-fault]

Is your feature request related to a problem? Please describe.
I'm trying to save and load the ContentStyle from some kind of file or similar. It's pretty weird to serialize it as bit integer in JSON.

Describe the solution you'd like
It would be much easier if Attributes implemented serde::Serialize and serde::Deserialize. Some kind of comma separated string of attributes enabled.

Describe alternatives you've considered if any
Serializing it using int.

Additional context
Right now I'm using it with Extism, but may use it for save/settings system.