feat(style): align with ts

[bdarcus]

property names

Change to camel case, but snake case values (for enums).

use untagged

Use serde untagged here and elsewhere.

https://github.com/bdarcus/csln/blob/0433e8d6161ead8e51accfeaf9533b560da3d9b6/src/style/template.rs#L26-L31

default values

The last two are related:

First , handle default values, be liberal in setting them, and getting rid of Option on fields:

https://graham.cool/schemars/deriving/attributes/#default

https://serde.rs/container-attrs.html#default

https://cj.rs/blog/rust-default-values-for-maintainability/

Example:

impl Default for Style {
    fn default() -> Self {
        Self {
            foreground: 0.4,
            background: 0.8,
            ...etc...
    }
}

Second:

Get rid of unwrap etc.

https://dmerej.info/blog/post/killing-unwrap/

The first automatically obviates need for this, but for those that remain, use other options like ?.