add MPRIS v2 metadata xesam:url

[wind-mask]

Describe what you want

Provide xesam:url in the MPRIS metadata.

Do you have already an idea for the implementation?

Refer to: https://www.freedesktop.org/wiki/Specifications/mpris-spec/metadata/#xesam:url

URI
URIs should be sent as (UTF-8) strings. Local files should use the "file://" schema.

[hasezoey]

That would likely be good, but the current version of the Media Control & Metadata crate we use does not have that functionality, but might in the next major version of it (see Sinono3/souvlaki#69 & Sinono3/souvlaki#66)